Jomini versus Clausewitz: Hamley’s Operations of War and Military Thought in the British Army,1866–1933

The First Edition of Operations of War (1866)

In the wake of the poor performance of the British Army during the Crimean War (1854–6), Lord Panmure, the Secretary of State for War, instigated a series of reforms designed to improve the training and education of the officer corps. In terms of British military thought, one of the most important developments to come out of this was the decision to mirror the way the French and Prussian armies used military history to provide officers with a standardized understanding of war. ¹⁶ This change came into effect when the Commander-in-Chief of the British Army, the Duke of Cambridge, ordered on 9 April 1857 that to hold a staff position, an officer needed to demonstrate that he was ‘thoroughly acquainted’ with ‘the principles of strategy’ and could explain them in relation to ‘campaigns of the ancient and modern commanders’. ¹⁷ In 1858 military history was included on the syllabus of the newly formed Staff College and also began to be taught to officer cadets at the Royal Military College, Sandhurst. ¹⁸

As these changes created a demand for books to assist those studying the military theory taught by the army, Hamley first approached Blackwood in early 1861 to explore the possibility of publishing his Staff College lectures. ¹⁹ By late April 1862 the scope of the proposed publication had grown and Hamley now intended to form this material into ‘an elementary essay on military science’. ²⁰ The reason for this was twofold. First, Hamley held a low opinion of the work used to teach military history, Major-General Patrick MacDougall’s The Theory of War (1856) and sought to replace it. ²¹ Second, following the commercial success of a biography of the Duke of Wellington he had written in 1860, Hamley believed there was ‘now an unusual appetite for military reading’ which he could capitalize on. ²² As such, from December 1862 to February 1865 the working title of his book was ‘The Common Sense of Military Art’; and, it was only several months before its publication that Hamley decided ‘The Operations of War: Explained and Illustrated’ would ‘do’. ²³

In the publication agreement, signed on 10 April 1865, Blackwood bore all of the risk of production while Hamley was awarded with 66% of any profit made, providing that he kept the book ‘up to date’. As Hamley insisted on a large number of maps, the cost of production was high. Thus, if the book was sold at 16/-, the rate originally proposed by Blackwood, it was expected to only make £140 for every 1,000 copies sold. As Hamley was unhappy at such a low rate of return, he argued that the price should be increased as he thought this was unlikely to influence how many were purchased. Thus, when the work did go on sale in 1866 it was priced at 30/-, and Hamley stood to make 9/9 for each volume sold. ²⁴

The book was divided into six parts, each made up of several chapters. The first section consisted of introductory material which explained how a ‘modern army’ depended on good roads, as these allowed it to manoeuvre and be supplied. The second part examined the ‘considerations which must precede the opening of a campaign’ hence discussing the selection of objectives and the differences between offensive and defensive warfare. The next three sections of the book dealt with strategy, which Hamley understood as the movements, or ‘operations’, of armies in a theatre of war. The final part of the work dealt with tactics and so focused on the employment of troops on the battlefield. ²⁵

Given both the volume’s provenance and its intended function, it reflected how strategy and tactics were explained to British officers during Hamley’s time at the Staff College. ²⁶ Consequently, although the work of the military theorists Archduke Charles and Henry Lloyd were mentioned, Hamley based Operations of War on Jomini’s writing as he considered him to be the ‘prince of strategists’. ²⁷ At the most fundamental level, the conception of strategy articulated in Hamley’s work was the same as in Jomini’s. Both thought that the conduct of operations should be subordinated to the war’s political end and that the military objective should be a geographical point of great importance. For Hamley, the latter should ‘generally’ be the enemy’s capital, as its capture ‘paralyses a civilised country’, and ‘is so ruinous that any terms [the occupier] may impose will generally be less pernicious than his presence’. He argued that this ‘material guarantee’ was necessary whether the cause of the conflict was the acquisition of territory or was ‘something less definite and tangible’. ²⁸

Hamley realized, like Jomini, that capturing the enemy’s capital would only have the desired effect if it was ‘coupled with such ascendancy over the defensive armies’ that they felt ‘further resistance was helpless’. Here, Hamley reverted to eighteenth-century precepts expressed in the writings of both Lloyd and Maurice de Saxe that successful strategy was not necessarily dependent on the destruction of the enemy’s forces. ²⁹ Instead, he argued that through manoeuvre an army could be placed in a position which either forced the enemy to ‘abandon territory under penalty of worse disaster’ or to fight a battle at a disadvantage. So, for Hamley, the ‘triumph of strategy’ was complete when a commander brought his adversary ‘into a position where the chances of victory are greatly against him’. ³⁰

This central idea had a considerable influence on how strategy was described in the rest of the work; and, here too, Operation of War was largely based on Jomini’s writing. The third part of the book placed an emphasis on the importance of supply lines in strategy, especially how to threaten an opponent’s communications while protecting one’s own. Although the fourth part of the work avoided ‘special reference’ to an army’s communications, it essentially articulated Jomini’s ‘principles of war’ as it focused on the necessity of concentration against the enemy’s weakest point. Here, particular attention was paid to the strategy of the central position, by which a numerically inferior army could gain an advantage over a divided larger opposing force by concentrating against each element of it in turn. ³¹ The final part of the work which dealt with strategy, part five, discussed the influence which obstacles, such as topography, had on the conduct of a campaign. As such, it served to provide examples which qualified the ‘operations’ described in the earlier parts of the work. Despite this, Hamley, like Jomini, avoided reference to any other issues which may have complicated the use of the manoeuvres he described, such as changing technology or psychological factors.

Another key similarity between Jomini and Hamley’s work was the way in which both authors used military history to provide ‘representative operations’ to explain to the reader each ‘principle or fact’ they sought to illustrate. Although Hamley did not use the same historical examples as Jomini when making similar points, both writers agreed that ‘modern military history’ was the best period from which to draw examples. In practice, for Hamley this meant campaigns conducted during or after the French Revolution, as the ‘copious records’ from this period lent itself to detailed study. Despite the focus on relatively recent events, this way of using military history led Operations of War to present strategy as essentially unchanging as campaigns fought decades apart were invoked to illustrate the same strategic principle. This effect was further created as this edition of the work made no reference to the influence which rail transportation or improving communications had exerted on strategy. As a result, the campaigns fought in the eastern theatre of American Civil War between 1861–2, which were profoundly influenced by these technological developments, were used along with the campaign of 1796 in Germany to illustrate the superiority of independent, as opposed to combined, lines of operation. ³²

Hamley frequently used examples from the American Civil War to illustrate Jominian ideas in Operations of War. For instance, he used General William Sherman’s operations against the General Joseph E. Johnston on the Chattanooga to show how threatening an enemy’s flank would cause them to fall back to protect their line of communication. ³³ Despite this, Hamley was privately highly critical of the Union forces, declaring to Blackwood that their defeat and panicked retreat after the first Battle of Bull Run in 1861 was ‘the greatest joke in the world’, and he hoped that ‘the cracks and flaws of the rotten old Union’ would lead to their defeat by the Confederacy. ³⁴ However, as he felt that it would be a ‘pity [to] say anything unpleasant [about] the Yankees’ which would harm his book’s sales in the United States, he limited his criticism of the Union to a censure of Sherman, claiming that he had moved too slowly against Johnston’s flanks. Hamley concluded that ‘no commander ever obtained a reputation equal to Sherman’s with so little actual fighting, and with such odds in his favour’. ³⁵

While the American Civil War featured prominently in Operations of War, reference to this conflict, which had been fought with modern rifled muskets, was noticeably less in Hamley’s discussion of tactics, contained in the sixth part of the work. The infantry tactics suggested were based on the formations employed during the Napoleonic wars; indeed, examples from this period were used to justify the continued deployment of troops in column and line on the battlefield. Hamley did not ignore the ‘introduction of the arms of precision’ but argued that they had not necessitated a ‘radical’ change in the use of infantry. In order to reach this conclusion, he downplayed the effectiveness of these weapons as the accuracy of men firing in a group was ‘very inferior’ to that made by individuals shooting at targets, on which ‘the calculation of the efficacy of rifle fire’ had been based. Clearly, both of these arguments ignored the recent experience of the American Civil War. Moreover, when discussing the employment of cavalry, Hamley also disregarded the events of this conflict. Instead, he sided with the ‘doctrine’ of the ‘Continental powers’ by arguing that cavalry, providing it was not exposed to fire for too long, was still able to successfully charge the front of enemy formations. ³⁶

Hamley’s book met with considerable commercial success for a work on military theory in Britain at this time as it sold over 1,000 copies in the two years after its initial publication. ³⁷ Hamley hoped that it could reach an international market and, in an attempt to stimulate a German translation, a copy was presented to General Helmuth von Moltke, Chief of the Prussian General Staff, in 1867. ³⁸ The work was praised highly by critics, and, although the reviewer in The Times noticed that the work concurred with Jomini on many points, he still claimed that as a military treatise it was ‘the best that has been written in the English language, and it may vie with any of its continental rivals’. ³⁹ The central role which Jomini’s ideas played in Operations of War reflected that the Swiss thinker’s work underpinned how strategy was understood in the British Army during the mid-nineteenth century. ⁴⁰ However, while this factor, together with the work’s high sales, paved the way for it to become a dominant force in British military education, the veracity of Jomini’s ideas would become increasingly challenged as the book went through a series of revisions over the next six decades.

Operations of War and British Military Thought, 1870–95

In the three decades following the publication of the first edition, Operations of War came to hold a central position in British military thought as it was selected as the textbook used to teach military history at the army’s educational establishments. Its adoption was due to its author holding a series of important posts, including a chair on the Council of Military Education, which set the books used for professional study by the army. ⁴¹ In 1870, when Hamley was appointed as the commandant of the Staff College, he made his work, along with Jomini’s Summary of the Art of War, the only ones to be set for the admission exam, a position they retained until 1895. ⁴² The way in which strategy was taught at the Staff College became increasingly centred on Hamley’s work; and, by 1876 the military history exam taken in order to graduate consisted largely of questions which asked students to ‘describe the method suggested in Operations of War’ to analyse the campaigns under study. ⁴³ In 1889 the examiner noted that on this paper no candidate ‘ventured to give a fact, to offer an opinion, or to make a statement, which is not to be found within the cover’ of Hamley’s work. ⁴⁴

In 1870 Operations of War was also adopted as the textbook used to teach military history at the Royal Military Academy at Woolwich, which trained officers destined for the Royal Artillery and Royal Engineers. Just as at the Staff College, the use of the volume had a profound effect on the content of the military history course, so by 1888 the academy’s library contained 16 copies of various editions of the work. ⁴⁵ The book also continued to play an important role at Sandhurst, and Winston Churchill recalled that he had purchased it to assist his studies at the College in 1894. ⁴⁶ After 1873, Hamley’s book was not the only text used to teach tactics by the army: C. Clery’s Minor Tactics was recommended, but mirrored the approach adopted in Operations of War as it too focused on variations of the ‘Napoleonic’ model of lines of infantry covered by skirmishers. ⁴⁷

As Operations of War dictated how the army approached the study of strategy between 1870 and 1895, the few other works produced for officers studying the subject were either based on Hamley’s volume or were intended to assist the comprehension of it. For example, in 1885 Mitchell & Co. published Colonel O.R. Middleton’s Outlines of Military History which consisted of campaign narratives intended to supplement those given in Hamley’s work for readers who did not have the time or ‘inclination’ to read more widely. ⁴⁸ The central position which Hamley’s work now occupied in British military thought did much to limit the publication and sale of other works on military theory in Britain. When in 1889 the publisher Macmillan & Co. approached the current Professor of Military History at the Staff College, Major-General John Frederick Maurice, for his opinion on whether they should publish their own military theory textbook, he advised against it. As Maurice explained, while Operations of War ‘gets a large sale because all those who are going up for examinations get it’, only a ‘very limited’ number of other works on this topic were sold due to the level of anti-intellectualism within the officer corps. ⁴⁹ This lack of interest in works not strictly necessary for exam purposes was reflected by the fact that the English translation of Clausewitz’s On War, completed by J.J. Graham in 1873, only sold ten to twenty copies a year between 1885 and 1900. ⁵⁰

One of the main reasons why Hamley’s work was able to maintain such a dominant position in how the army studied war was due to the author’s obligation to ‘keep the book up to date’ in his publication agreement. Hamley first felt the need to revise his work following the Austro–Prussian War as ‘the first edition … chanced to be published just before the occurrence of events which marked the end of one era, and the commencement of another, in the operations of war’. ⁵¹ However, in order to avoid a financial loss, as a new edition would make the original seem obsolete, Hamley agreed with Blackwood to wait until 1,000 copies of the initial print run of 1,500 had been sold before making revisions. ⁵² Hence, it was not until October 1868 that work on the new edition was begun in earnest. ⁵³

While the changes Hamley made for the second edition, which appeared in late 1869, did not affect the general lay-out of the work, he altered those parts which dealt with strategy to include reference to the influence of railways and telegraph communication. ⁵⁴ Nevertheless, Hamley largely downplayed there effect and, as he privately admitted to Blackwood, his alterations to these portions of the text only constituted two or three pages. ⁵⁵ He argued that railways ‘need be regarded only as roads giving increased facilities of movement’ and that the telegraph had the potential to allow a commander to combine his forces more effectively, but that there had been no historical example of this. As a result, Hamley felt that these developments had not altered the Jominian principles on which the portions of the work on strategy were based. ⁵⁶

There were, however, more significant revisions made to the section on tactics, as this was ‘in great part rewritten’ due to the use of the breech-loading rifle in the Austro–Prussia War which had added ‘rapidity of fire … to that of precision’. As Hamley felt that these new arms had made ‘the manoeuvres of [the] former era … in great measure obsolete’, he thought ‘light infantry duties’ to be ‘more than ever important’. He also added a section on the importance of entrenchments as, despite overlooking the experience of both sides during the American Civil War in the first edition, he now argued this conflict had demonstrated that ‘the value of these [had] increased’ as infantry firepower improved. ⁵⁷

Hamley revisited his treatment of the American Civil War as in April 1867 he received a letter from Sherman intended to induce him to ‘modify’ his chapter on the general’s operations in Georgia. Even though Hamley admitted to Blackwood he had ‘always been prejudiced against Sherman, on account of the barbarous way in which he made war’, he included a copy of the general’s letter in the chapter and removed all criticism of him from the text. Evidently Sherman was pleased with the corrections because, when in May 1870 the US Military Academy at West Point and the US Army’s Artillery School began ordering the book directly from Blackwood, Hamley put this down to his intervention. ⁵⁸

The third edition of Operations of War, published in the final months of 1872, incorporated the changes Hamley felt necessary after the Franco–Prussian War, and likewise presented strategy as little changed. ⁵⁹ As a result, the new chapter he added on the opening campaigns of this conflict simply provided a historical overview of the campaign which was used to further illustrate Hamley’s ‘principles’. Once again, the largest alterations to the work were made in relation to its discussion of tactical matters and this rewritten. He now argued that as the increase in infantry firepower had made a frontal attack ‘costly and doubtful’, a ‘flank attack’ was ‘essential’. The Franco–Prussian War had also altered Hamley’s views on the employment of cavalry as he thought the opportunities for their use on the battlefield was ‘rare’, as there had been ‘no example of such attacks in the campaign of 1870’. Furthermore, Hamley now contended that fortresses were becoming ‘untenable’ due to the increasing range and power of modern artillery as the ‘war of 1870 conclusively proved’. ⁶⁰

The final revisions made by Hamley to Operations of War were begun in October 1877 and appeared in the fourth edition of the work, which was published in early 1878. ⁶¹ Unlike previous revisions, Hamley’s discussion of tactical matters was almost unchanged; instead, as he felt operations during the Russo–Turkish War (1877) had demonstrated that technological developments had modified one of Jomini’s principles, it was the part of the work which dealt with strategy which underwent an important alteration. He argued that this conflict had demonstrated that the electric telegraph allowed a commander of divided forces to successfully coordinate against a concentrated opponent, so the ‘disadvantage’ connected with a double line of advance had been ‘diminished’. To illustrate this, Hamley pointed to General Ivan Lazarev’s use of his telegraph to coordinate an attack on a Turkish position in October 1877, even though elements of his army were over 40 miles apart. ⁶²

The use of Operations of War at the army’s training establishments, combined with the regular revisions, helped it to maintain good sales throughout the 1870s, and the third edition, for instance, sold over 1,000 copies in the 12 months ending in February 1874. ⁶³ However, while a fifth edition was published in 1886 to correct small typographical errors, no further revisions to the work’s substance were made until 1907. The reason for this was that between 1882 and his death in 1893 Hamley lost interest in military affairs as he was engaged in a bitter public feud concerning his conduct during the British invasion of Egypt with General Sir Garnet Wolseley. ⁶⁴ Therefore, although the 1878 edition had introduced the notion that changing military technology could undermine the ‘operations’ described therein, by the early 1890s Operations of War had not been significantly revised for over a decade. The lack of a new edition, combined with the fact that Hamley no longer occupied influential posts within the army due to his dispute with Wolseley, caused the sale of the work to decline, especially following the cancellation of the US Army’s annual order in 1882. ⁶⁵ This created scope for the authority of Operations of War to be challenged and the ideas of other military theorists, particularly Clausewitz, to be introduced into how war was studied by the army.

The Sixth Edition and Clausewitz, 1895–1914

In 1893 Colonel G.F.R. Henderson was appointed Professor of Military History at the Staff College. He set about reforming the way war was conceptualized at this institution as the success of the Prussian Army under von Moltke against the Austrians and the French caused him to look to German military writers. ⁶⁶ First, Henderson changed the justification for studying military history to reflect Clausewitz’s argument that the subject should be used to analyse decisions made by commanders, allowing students to develop their own military judgement. For this reason, Henderson criticized Operations of War since it considered only the ‘elementary’ and ‘mechanical’ building blocks of strategy but ‘scarcely mentioned’ the ‘higher art of generalship’. Second, Henderson produced a list of 21 ‘strategical principles’, which contained ideas derived from both Clausewitz and Jomini, as the framework through which he expected students to think about war. These ‘principles’ began by setting out a more Clausewitzian relationship between strategy and policy, stating that they must be ‘in harmony’. As a result, the definition of ‘strategy’ used at the Staff College now became ‘the use of combats for the object of the war’ as this directly corresponded with that given in On War. ⁶⁷ Henderson’s principles also placed an emphasis on psychological factors in war, as the Prussian had done, referring to them using Napoleon’s maxim, ‘the moral is to the physical as three to one’. When it came to defining the military objective, it is likely that Henderson was again influenced by his understanding of On War and the emphasis placed on decisive battle in contemporary German military thought, as he stated this should be the ‘enemy’s main army’. ⁶⁸ Elements of a Jominian understanding of strategy remained as there was also an emphasis on axioms which related directly to the movement of armies in a theatre of war. Nevertheless, Henderson’s ‘principles’ did not solely rely on the writing of Jomini and Clausewitz because while neither writer had focused on maritime considerations, his list stated that ‘command of the sea’ was an important factor in war. ⁶⁹

Following the poor British showing during the Second Boer War (1899–1902), the army again turned to the study of military history in an attempt to improve the professional outlook of the officer corps. In 1904 the subject was added to the exams sat for promotion from Lieutenant to Captain and from Captain to Major. ⁷⁰ The syllabus of these new exams, together with the curriculum of Sandhurst and Woolwich, was altered so that it mirrored the approach to understanding war now employed at the Staff College. ⁷¹ Likewise, Field Service Regulations 1909, the manual intended to describe the army’s doctrine, published several years later, also described war in alignment with Henderson’s ‘strategical principles’. ⁷² Given the increasing importance of Clausewitz’s ideas in British military thought, a version of Graham’s original translation of On War, edited by F.N. Maude, appeared in 1908 and sold 573 copies in this year alone. ⁷³ By contrast, as Operations of War did not reflect these advances in military thought, and so was of little use to those studying to take army exams, its sales collapsed. While between December 1899 and June 1904 Blackwood sold 2,304 copies of the work, only 435 were purchased between July 1904 and June 1907. ⁷⁴

In an attempt to improve the work’s sales, Blackwood asked several military authors how it ‘might be brought up to date’ to reflect how the army expected officers to think about war. ⁷⁵ In April 1906 Major-General Launcelot Kiggell, then a lecturer at the Staff College, agreed to edit the book and when he was appointed as Assistant of Staff Duties on the General Staff on 1 January 1907 he took a ‘month’s “Hamley” leave’ to make his revisions. ⁷⁶ Kiggell sought the help of several fellow officers, including Colonel C.E. Callwell, author of Small Wars (1896), a theoretical text on asymmetric warfare, but made all of the changes to the text himself. ⁷⁷ Kiggell also requested advice from the Secretary of the Committee of Imperial Defence, Sir George Sydenham Clarke, although he rejected his proposal for a chapter on British ‘Imperial Strategy’ since Operations of War ‘purports to deal with war in general’ not Britain’s ‘particular case’. ⁷⁸

Despite this, Kiggell made numerous significant alterations to the work. Not only did he replace its sixth part, which originally dealt with tactics, with a detailed analysis of the Russo–Japanese War (1904–5), which regularly featured on army exams, but he also reframed Hamley’s discussion of strategy. Kiggell placed a much greater emphasis on war as ‘a political instrument’ and the reader was reminded of the importance of distinguishing between the political objective, which a government had gone to war to achieve, and that sought by the military. The work’s previous contention that the ultimate aim of strategy was the capture of the enemy’s capital was overturned as ‘only in very exceptional cases’ would the ‘mere occupation of some important point… induce the hostile government to sue for peace’. Instead, Kiggell stated that ‘the first military objective must, therefore, almost unvaryingly be the complete defeat of the enemy’s force in the field’. This reframing of strategy relied on its ‘interdependence’ with tactics as ‘only great tactical successes can lead to great strategical ones’. He underscored this departure from Hamley’s Jominian conception of strategy by invoking Clausewitz’s On War as the theoretical authority which supported these alterations. To assuage any doubts the reader may have had regarding the Prussian’s veracity, they were assured that by ‘quoting Clausewitz we are quoting the authority on whom, above all others, Moltke based his action and his teaching’. ⁷⁹

This revised conception of strategy received a full illustration in the new section on the Russo–Japanese War. Unlike the campaign narratives provided by Hamley, Kiggell’s analysis of this conflict began with an examination of the political objectives and alliances of each side. The explanation of the operations was made in relation to both these political considerations and the notion that the enemy forces ‘must’ be the objective. The selection of this campaign for analysis also allowed the influence of sea power on the land campaigns to be considered. Indeed, Kiggell believed that ‘one of the most valuable lessons to be learnt from the war’ was how the army and the navy ‘can mutually help each other … under present day conditions’. ⁸⁰

Although Hamley had entirely ignored the effect of psychological factors in warfare, Kiggell’s description of the Russo–Japanese War placed great emphasis on them. He argued that the ability of an army to ‘bring superior force to bear at a decisive point and time’ depended ‘more on moral than physical qualities’, as he believed superiority in this regard not only enabled a force to march faster and further than its opponent, but also gave it an important advantage in battle. Clausewitz was quoted to demonstrate that the personal ‘character’ of the commander, particularly his combination of ‘moral and physical’ courage, together with a knowledge of how to excite the ‘enthusiasm’ of his men, had ‘always’ been more important than his military skill in bringing about success. This led Kiggell to conclude that the Japanese victory had stemmed from their ‘energy, endurance and resolution’. ⁸¹

Kiggell also broke with Hamley’s purely illustrative use of military history in this section. Instead, he mirrored the approach to studying the subject advocated by Clausewitz, directly posing questions to the reader asking them to consider the correct course of action in key moments of the campaign. For example, after describing the situation faced by the Russian commander, General Aleksey Kuropatkin, the reader was asked, ‘what is a general placed in such a predicament to do?’ Kiggell followed this with an examination of the strengths and weaknesses of each possible course of action. ⁸²

Given the new emphasis on the close relationship between strategy and tactics in the work, the treatment of the latter assumed a greater importance. Kiggell’s replacement for Hamley’s section on this topic, entitled ‘Notes on the Study of Tactics’, did away with the discussion of formations and instead stressed that while ‘new inventions’ had necessitated the continual development of tactical methods, history had shown that tactics, like strategy, were based on ‘great fundamental principles’. ⁸³ However, the ten tactical ‘principles’ Kiggell proposed were more conceptual than they were prescriptive, reflecting Clausewitz’s notion that theory should be a guide to understanding, rather than a set of axioms which dictated the action of a commander. ⁸⁴ The list began by stressing the importance of ‘moral attributes’ and the ‘influence of the commander’, before moving on to more practical considerations such as ‘mobility, combination and firepower’, ‘time’, ‘reserves’, the need to accept ‘losses’ and ‘the relationship between attack and defence’. The final principle, ‘surprise’, also underscored how much Kiggell relied on Clausewitz’s writing; to demonstrate its importance, he quoted a passage from On War which argued surprise ‘lies more or less at the foundation of all undertakings, for without it the preponderance at the decisive point is not properly conceivable’. ⁸⁵

Despite the changes to the way strategy was reframed in the first two parts of the work, most of the other sections of Operations of War remained strongly influenced by Jomini’s writing. Critically, parts three, four, and five, in which Hamley described the various ‘operations’ armies could undertake, remained essentially unchanged. In the chapter on the Russo–Japanese War, Kiggell described the manoeuvres made by both sides in relation to the sections of the book which dealt with strategy. Thus, for example, Kuropatkin was praised as, in July 1904, he occupied a central strategic position enabling him to ‘act offensively against each of the Japanese armies’ opposing him. ⁸⁶

In short, the revisions Kiggell made to Operations of War reflected that a combination of Jominian and Clausewitzian ideas now underpinned how the army expected officers to understand war. As the work once again reflected the army’s exam syllabus, its sales partly recovered, and between July 1907 and June 1914 Blackwood sold 2,134 copies. ⁸⁷ Since the army had not used Operations of War as the only textbook to study military history since 1895, scope had been created for other publishers to produce competing volumes: as a result Hamley’s work was unable to regain the sales it had enjoyed in the 1870s. ⁸⁸ While Kiggell’s revisions demonstrated that Hamley’s work had ceased to hold a central position in military thought, as it no longer determined how war was understood, it still continued to exert influence on high-ranking officers. As French regularly quoted from Operations of War in his orders, in July 1907 Blackwood agreed to Kiggell’s suggestion that a free copy of the latest edition should be sent to him. ⁸⁹ Although French’s use of the work at the start of the First World War is testament to its continued influence on British military thought in 1914, during the interwar period Operations of War came to be seen as increasingly anachronistic and fell out of use.

‘Ludicrously Out of Date’: The Final Edition (1919–36)

Soon after the end of the First World War, the copyright holder for Operations of War, Hamley’s niece, Lady Barbara Ernle, begin to organize the work’s revision. Even though the 1907 edition was selling ‘slowly’, with only 117 copies sold on average each year between 1916 and 1921, on French’s advice the publisher decided to delay revising the work until an understanding of the conflict could ‘crystallize’. In 1919, Blackwood and Ernle began to search for a military figure to edit the work, unsuccessfully approaching Kiggell, Major-General Ernest Swinton, General Sir George M. Harper, and General Ian Malcolm. ⁹⁰

The search for a suitable editor ended in April 1920 when Ernle reached an agreement with Major-General Sir George Aston, author of several books on maritime operations and Staff College lecturer between 1904 and 1907. ⁹¹ The availability of reliable information concerning operations during the First World War severely delayed Aston’s progress as he was forced to redraft his corrections three times as new evidence became available. He was, therefore, ‘anxious not to complete [his] comments on the Great War … until the last possible date’, and so only submitted the final version of the manuscript on 14 September 1922 as the old edition was almost out of print. These delays meant that the seventh edition of Operation of War was not published until late January 1923. ⁹²

The first five sections of the work received little revision, although Aston did briefly refer to how changing military technology influenced strategy. The reader was told ‘caterpillar’ tracks and motor vehicles had dramatically increased the mobility of armies, field telephones had improved the speed information could be passed and aircraft would assist in the observation of the enemy. He argued, however, that although in the last century ‘there had been a vast change in the relationship between time and space in strategical problems’, the ‘operations’ described by Hamley had ‘endured as guides for the modern strategist’. In this way, strategy continued to be described in relation to a set of Jominian axioms which referred to manoeuvres made by armies in a theatre of war. Aston underscored how little he thought strategy had changed as he drew on events from the First World War to demonstrate some of Hamley’s principles. For instance, while the ability of railways to rapidly reinforce an army was originally illustrated by reference to the American Civil War, it was now supported by the ‘290 troop-trains’ used to concentrate British forces immediately prior to the battle of Amiens in August 1918. ⁹³

The most significant changes made by Aston appeared in the book’s sixth section, which now contained four chapters. The first provided analysis of several ‘modern wars’ fought between 1866 and 1905, including the Russo–Japanese War, although the treatment of this conflict was reduced. The second chapter considered the First World War, and the final two discussed tactics. When analysing the First World War, Aston echoed the work’s description of the object of strategy by identifying the ‘main German Army’ on the Western Front as the military objective for Britain and France. He was critical of the many operations undertaken by the ‘allied side’, such as those against Turkey, which were ‘for political rather than for military objects’, since this diverted resources from the vital theatre of war. Despite this line of argument, Aston did not discuss operations on the Western Front between 1915 and 1918 in any depth. The major battles of Verdun, the Somme and Third Ypres were not even mentioned, let alone analysed. He failed, furthermore, to examine many factors, such as industrial production and manpower management, which had had a major influence on the higher direction of the war. Equally, as Aston had barely revised Kiggell’s chapter on tactics, it did not consider the Western Front’s major battles, nor did it refer to tanks, aircraft, or artillery developments. ⁹⁴

The seventh edition did not sell well, and between 1923 and 1932 Blackwood only sold, on average, 77 copies a year. ⁹⁵ Following the death of Ernle in November 1930, her husband requested that the work should be reprinted as a ‘memorial to her uncle’. ⁹⁶ As Blackwood felt there was no business case for this, Lord Ernle agreed to pay two-thirds of the cost incurred in reprinting 500 copies in March 1933. ⁹⁷ The work continued to sell in small numbers as the seventh edition was specifically prescribed as a textbook used to study the Peninsular War at Oxford University until 1951, when it was removed from the reading list by the Chichele Professor of the History of War, Captain Cyril Falls. ⁹⁸ As it had become evident that Operations of War was unlikely to ever make money in the future, on 15 September 1936 the plates used to print the work were broken up. ⁹⁹

The main reason for the decline in sales was due to developments in British military thought during the 1920s which led war to be considered in fundamentally different terms to those described in Operations of War. When a new edition of Field Service Regulations was published in 1920 it contained a list of ‘principles of war’ derived from the writings of Colonel J.F.C. Fuller. A similar list also appeared in the Field Service Regulations of 1924, and in the 1929 edition these principles were defined as: concentration, economy of force, surprise, mobility, offensive action, cooperation, and security. ¹⁰⁰ As the army now expected officers to think about war in relation to these factors, ensuring that they were understood became an important consideration in the army’s military history syllabus. By 1924 most of the questions on exams set for officer promotion in this subject were based on the application of these principles, which were not mentioned in Operations of War, to historical examples. ¹⁰¹

The ‘principles of war’ in Field Service Regulations represented the acceptance of a Clausewitzian approach to military theory, designed to be a guide to understanding war, and a rejection of the Jominian positive system which underpinned Hamley’s work. ¹⁰² This shift, and the reasons behind it, were explained in several volumes published during the 1920s which received the imprimatur of the Chief of the Imperial General Staff. ¹⁰³ One such work, Major-General Sir Frederick Barton Maurice’s British Strategy: A Study of the Application of the Principles of War, published in 1929, was highly critical of Operations of War as neither ‘Jomini [n]or Hamley’, considered more than the ‘various forms of strategical manoeuvre’ employed by armies. Instead, Maurice explained that an understanding of strategy must now not only integrate the use of air and sea power but should also go beyond thinking about war in purely military terms. As war was a ‘political act’ and a ‘social cataclysm’, its political objective should ‘govern the naval, military and air objects’ so strategy should be thought of as ‘the art of applying national power to achieve the object of the war’, rather than simply the defeat of the enemy’s army, as the most recent editions of Operations of War had defined it. This departure from the Jominian understanding of war was underscored when Maurice described Clausewitz as ‘the father of modern strategical study’ and did not include either Hamley or Jomini when listing the most influential military theorists. ¹⁰⁴

Besides these problems concerning how war was conceptualized, Aston’s edition of Operations of War faced more practical difficulties which further limited its utility for officers taking army exams. First, in the interwar period the campaigns studied by the army changed considerably and included many British operations from the First World War not examined by Aston, such as those in Palestine and on the Western Front in 1915. ¹⁰⁵ Second, the army’s syllabus now also included colonial ‘small wars’ which had not been addressed in any edition of Hamley’s work. ¹⁰⁶ Third, there was now greater competition from other works designed to assist officers sitting exams, such as Major H.G. Eady’s Historical Illustrations to Field Service Regulations, which went through a series of revisions in 1924, 1926, 1927, and 1930, to ensure it directly mirrored the syllabus. ¹⁰⁷ The difficulties Operations of War now faced in a more competitive book market were compounded as the 1923 edition had been heavily criticized by reviewers when it first appeared. The review contained in The Times Literary Supplement in February 1923 was especially damning as it described the work as ‘ludicrously out of date’ since its coverage of the Great War made no reference to ‘trench warfare, breakthrough, strategic devastation’, poisonous gas or tanks. ¹⁰⁸

Given the previous authoritative position Operations of War had held in British military thought for many years, the work was occasionally referenced in the interwar period, usually in relation to the Russo–Japanese War. As Aston had significantly reduced the analysis of this conflict, when Eady referred to the work in his Illustrations to Field Service Regulations, his references corresponded to the 1907 edition. ¹⁰⁹ Equally, when the Russo–Japanese War featured in the army’s promotion exams in 1925 and 1926, the examiner’s comments also referred to this edition. ¹¹⁰ However, as the 1930s progressed, Operations of War fell out of use and so when the Russo–Japanese War returned to the army’s promotion exam in 1937 no reference was made to the work. ¹¹¹

Conclusion

To recapitulate briefly, the main reason why Operations of War was able to occupy an influential position in British military thought for over 50 years was due to the prestige the work gained by providing the army with a standard way of conceptualizing war between 1870 and 1895. The fact that the book was able to hold such a central position owed much to its use as the sole textbook employed by the army to study history, and so teach military theory to officers. ¹¹² The work’s longevity was further extended by Kiggell’s amendments, made in 1907 for the sixth edition, as they caused the work to reflect the increasing influence of Clausewitzian ideas on British military thought. As this trend continued after 1918, and war came to be understood by the army as a societal phenomenon which constantly changed in character, by the late 1920s Hamley’s work was seen as obsolete. ¹¹³ Therefore, although Aston was forced to rush his alterations, and could not make extensive changes as Kiggell had done, this had little to do with why the work fell out of use. The modifications necessary to make Operations of War mirror the latest advances in military thought would have required such a fundamental change in its character that it would have been no longer based on Hamley’s original text.

This transitional period in which British military thought shifted from a Jominian to a Clausewitzian way of understanding war gives Operations of War a greater significance since the revisions to the work, and why it fell out of use, reflect how this change took place in some detail. Although the army’s use of a combination of Jominian and Clausewitzian ideas from the 1890s meant that Hamley’s work no longer determined military thought, the 1907 edition of the book demonstrated that the writing of these two theorists was thought to be far from incongruous. In this regard, the work reflected the view put forward in 1891 by Spenser Wilkinson, who became the first Chichele Chair of Military History at Oxford University in 1909, that Clausewitz ‘differed from Jomini, not in disagreeing with his theorems, but by laying the chief stress on matters which in Jomini’s work appear to be secondary’ so that ‘the two writers thus supplement one another’. ¹¹⁴ Therefore, despite Azar Gat and John Alger’s view that the Prussian’s work had little influence on British military thought prior to the First World War, the 1907 edition of Operations of War reflected that not only were Clausewitzian ideas present, but that they were entrenched by this time. ¹¹⁵

In fact, beyond simply illustrating this transition between a Jominian and Clausewitzian understanding of war, Hamley and Operations of War did much to delay it. After Hamley vacated the position of Professor of Military History at the Staff College in 1865, the Prussian’s work briefly began to influence study there. Colonel Charles Chesney, the new Professor of Military History, incorporated Clausewitz’s approach to the critical analysis of military history and directly invoked his judgements on the campaigns under study. ¹¹⁶ However, following Hamley’s appointment as commandant of the Staff College in 1870 and his adoption of Operations of War as the textbook used to study strategy, reference to Clausewitz’s ideas ceased, and the focus reverted to Jomini. ¹¹⁷ Although Hamley may have made this decision solely due to his Jominian understanding of war, the financial incentive for him to employ his own work meant that he encountered opposition from the other members of the Council of Military Education, and they even temporarily blocked the use of Operations of War at Woolwich. ¹¹⁸ Hamley overcame this obstruction by asking the Commander-in-Chief of the army, his personal friend, to ‘waive’ their objection since there were so few works of military theory in English which could be used instead. ¹¹⁹ This incident not only underscored the instrumental role Hamley played in ensuring his work achieved its influential position, but also the poverty of military thought in Britain prior to the First World War.

It was the combination of Jominian and Clausewitzian ideas, which described the destruction of the enemy’s army as the main objective in strategy, that British officers took into the First World War. ¹²⁰ This may explain why Field Marshal William Robertson, Chief of the Imperial General Staff for much of the conflict, favoured the German Army on the Western Front as the main strategic objective. ¹²¹ Robertson, as Commandant of the Staff College between 1910 and 1914, held a copy of Henderson’s ‘principles’ from March 1912 in his possession. ¹²² Equally, as the copy of Operations of War purchased by Churchill in 1894 did not stress the need to defeat the enemy’s forces, instead suggesting they could be outmanoeuvred, allowing key locations could be captured, it may have influenced his decision-making as First Lord of the Admiralty between 1911 and 1915. ¹²³ Most notably, in justification for his support for the Dardanelles operation in 1915, Churchill argued that the main bulk of the enemy’s forces did not need to be directly defeated, only that his ‘flanks’ should be turned and attacks launched at the ‘least guarded of strategic points’. ¹²⁴

Besides the relationship between the ideas of different theorists in Operations of War, Hamley’s volume also reflected a growing tension which faced British military writers regarding whether they should employ continental approaches to understanding war, or should instead develop a method specific to the British case. ¹²⁵ The editions of Operations of War compiled by Hamley firmly represented the adoption of continental methods, as although the British Army only fought colonial conflicts between 1866 and 1914, this type of warfare was ignored in the work as its author did not consider it worthy of study. ¹²⁶ This represented a significant problem with officer education in this period as the ‘small wars’ fought by the army did not readily lend themselves to a Jominian framework. As Callwell identified, Hamley’s description of strategy was based ‘on communications’ and so was of limited utility against, for example, ‘Maories or Afghans’ who ‘possess no communications and require none’. ¹²⁷

Nevertheless, by the end of the nineteenth century this way of thinking about strategy came to be challenged as a greater emphasis was placed on developing a system to address the problems Britain faced. By the late 1890s Henderson had included ‘command of the sea’ in his ‘principles’ and Callwell’s Small Wars had been published. While Kiggell rejected the idea of referring directly to British ‘Imperial Strategy’ in the changes he made to Hamley’s book, he did focus on the Russo–Japanese War. ¹²⁸ As this conflict pitted an island nation with a powerful navy and a small army against a major land power, it served as a medium through which the British situation in a European war could be considered. ¹²⁹ After the First World War, the emphasis on developing a British approach to strategy continued, further underscoring how irrelevant Hamley’s work had become. Not only was the title of Maurice’s British Strategy deliberately chosen, but in his forward to the work, the Chief of the Imperial General Staff stressed the need to avoid ‘dogmatically’ applying the ‘ideas of continental writers’ as they did not address the ‘situations’ likely to affect the British Empire. ¹³⁰

The revisions made to Hamley’s work also reflected the growing tension in British military thought between continuity and change in war. Although the first five editions were deemed necessary due to technological developments, Hamley’s amendments stressed continuity in strategy and tactics. The alterations he suggested to tactics did not break the ‘Napoleonic model’ of lines of infantry supported by skirmishers, nor was the improvement of weapons seen as having an effect on strategy. ¹³¹ Similarly, in the fourth edition of 1878, the telegraph was only seen as reducing the danger associated with a double line of advance, rather than removing it entirely. ¹³² Kiggell’s revisions, forming the 1907 edition, embraced change in war to a greater degree. Although he thought strategy was not fundamentally altered by technological developments, tactics were seen as so changeable a framework of conceptual principles was required to study them. Furthermore, by looking at the latter stages of the Russo–Japanese War, Kiggell speculated that the increasing power of weapons, combined with strong defences and large armies with extended fronts, could lead to prolonged battles in the future, influencing strategy. However, he downplayed the likelihood of this as he deemed it a ‘most unlikely’ occurrence in Europe. ¹³³ While the 1923 edition of Operations of War emphasized continuity in strategy, after the First World War British military thought placed a much greater stress on change in war. ¹³⁴ This focus was partly due to the rapid development of weapons technology during the conflict, but was also because war was now seen as a social phenomenon and so inherently changeable. ¹³⁵

Ultimately, Hamley’s Operations of War provided a degree of continuity in the British Army’s military thought for over 50 years, even as the character of war underwent major changes. It was able to do this as the ‘operations’ the work described served as a connection between strategy and tactics, and so provided the foundation for the army’s study of ‘operational art’, as this term was understood in the late nineteenth century. ¹³⁶ Nevertheless, the greatest significance of the work is that it reflects how the army’s understanding of war developed during this time in some detail, particularly how Clausewitzian ideas were originally integrated. And, for this reason, Operations of War deserves the attention of historians of both the British Army and of military thought.