Allied blockade in the Mid-East Atlantic during the First World War: cruisers against commerce-raiders

The need for an Allied blockade in the Canary Islands area

On 6 August 1914, the Spanish authorities disabled the radiotelegraph stations of foreign ships anchored in Las Palmas, Gran Canaria. They also proceeded to seal the huts and lower the antennas of these stations because of the complaints made to the government, such as that made by the French ambassador, who claimed that from Las Palmas they communicated to the German warships the movements of French merchant ships in the port. The French Embassy requested that the use of these radiotelegraph devices be prevented, along with the irregular loading of provisions and coal carried by German ships to supply their warships. ²

In addition, since the beginning of the war, Allied diplomatic representatives coordinated their actions closely with the Spanish authorities to jointly pressure and prevent the use of the islands by German ships. Thus, in the first days of August 1914, the French and British consuls protested to the government delegate in Gran Canaria about the excess coal taken by the German ships Ingo and Arucas in Las Palmas. ³ The governor of the province telegraphed the authorities of Las Palmas ordering strict surveillance, supporting the protest of Swanston, the British consul in Las Palmas, ⁴ who communicated the movements of German ships to intelligence centres and believed that the port of Las Palmas was used to obtain coal and supplies to be transferred to armed German ships. ⁵ For his part, the British ambassador voiced his support of Swanston’s requests to prevent the clandestine supply – incompatible with Spanish neutrality – of German and Austrian ships at anchor in Las Palmas. ⁶ Their suspicions were confirmed on 22 August, when the steamship Arucas left Las Palmas with 1,500 tons of coal to supply the Kaiser Wilhelm der Grosse in Río de Oro, which transferred 187 prisoners, mostly English, to Arucas, which returned to the port of Las Palmas. ⁷

In September, several clearances of ships with provisions for the coast of Africa from the ports of Agaete (Gran Canaria) and Las Palmas were suspended by the Navy commander, who suspected that the supplies were destined for the German warships Dresden and Karlsruhe, which were believed to be close to the Canary Islands, when a radiogram sent to them was intercepted at Las Palmas. The sending of a coded radiogram issued for the German cruiser Karlsruhe from the radiotelegraph station of Melenara, Gran Canaria, motivated the complaint of the British ambassador, who – on behalf of the Secretary of State for Foreign Affairs – requested that the local government of the Canary Islands be reprimanded to avoid the repetition of this abuse of Spanish neutrality. ⁸ The complaints of the consuls of Britain and France on this matter – communicated to their respective ambassadors – added that the Germans were hoarding large quantities of potatoes throughout the island. ⁹

Additionally, in Santa Cruz de Tenerife, the British consul asked the Spanish authorities to investigate the movements and destination of the German steamship Telde before allowing it to leave port with excess coal. ¹⁰ The departure authorization granted to the ship, suspected of intending to supplying coal to German cruisers, provoked complaints from the British Embassy, which held the Spanish government responsible for the consequences that could result from it and questioned the impartiality of the local authorities. ¹¹

In October 1914, communications from the Allied diplomacy regarding German ships at anchor in the Canary Islands multiplied. On 9 and 21 October, the French and British ambassadors, respectively, requested that the Norwegian steamers Nepos and Mowinckel be prevented from leaving Santa Cruz de Tenerife. The previous month they had arrived at this port from United States, with German pursers and a cargo of coal that they suspected was destined to supply a German warship, since letters intercepted by British censors seemed to indicate so. ¹²

That month, the French and British ambassadors drew the attention of the Ministry of State to the acting director of the free port of Las Palmas, whom they accused of being a Germanophile for facilitating the shipment of 200 sacks of potatoes on the German steamer Arucas to supply the Kaiser Wilhelm der Grosse. ¹³ Although the Ministry of Finance assured the State Ministry that it would accelerate the inauguration of the new official, the French would reiterate their complaints about a new shipment made on Arucas – interned in Las Palmas – which they claimed was destined for a German warship. ¹⁴

On 22 October, the day after the clandestine departure of the German steamer Walhalla from Las Palmas, the French ambassador requested that Spanish neutrality not be violated by the transfer of goods that constituted war smuggling between Norwegian ships and the Walhalla, now in Santa Cruz de Tenerife. The ambassador recalled that the German steamer had left Las Palmas for Montevideo on 2 August, supplying the auxiliary cruiser Kronprinz Wilhelm, and had returned on 25 August with sailors from that cruiser. ¹⁵ Although the governor of the province informed the British authorities that Walhalla arrived in Tenerife without having been dispatched by the authorities of Las Palmas, and it had been fined according to the provisions of the law for such cases, ¹⁶ the Admiralty considered it necessary for the British ambassador in Madrid to urge the Spanish government to officially intern the steamer. ¹⁷

Both the British and French ambassadors requested that the Walhalla be considered an auxiliary of the German Navy and be interned for good. In support of this request, they argued that the Walhalla had made provisions to the Kronprinz Wilhelm in the vicinity of the Azores and had taken to Las Palmas prisoners of war captured by German cruisers in the Atlantic. ¹⁸ The Minister of the Navy would eventually give the order to intern the Walhalla in Santa Cruz de Tenerife. ¹⁹ The engines of the steamer were disabled, and, guarded by the Spanish gunboat Laya, it was transferred on 8 January 1916 from the port of Santa Cruz de Tenerife to Las Palmas to ensure its safety in times of storm. ²⁰

The British adopted a similar stance when the German steamer Crefeld arrived in Santa Cruz de Tenerife on 22 October 1914, ²¹ driving 419 crew members from 13 ships captured by the Karlsruhe. On 3 November, the captain of the port of Santa Cruz informed the British consul that the Crefeld had been interned for the time being. ²² Although the local authorities had given assurances that it would not be allowed to leave, the Admiralty did not consider this measure entirely satisfactory, so the Admiralty asked the British ambassador to urge the government of Madrid to officially intern it. ²³ Ambassador Hardinge reiterated his previous requests on this matter. The rumour had reached the British that the German steamer Cap Ortegal, anchored in Santa Cruz de Tenerife, had weapons on board and would relieve Crefeld in assisting the German fleet. The British government requested that Crefeld be interned and Cap Ortegal inspected. However, Spanish authorities inspected both vessels and found no weapons on board. ²⁴

As with Walhalla, Spain’s naval authorities ended up considering the Crefeld an auxiliary ship and determined that it should be interned in the port of Santa Cruz de Tenerife, ²⁵ where it would continue to be the object of British surveillance. Additionally, around that time, the French Ministry of Foreign Affairs told its ambassador in Madrid to draw the attention of the Ministry of State to the negligent attitude of some authorities of Las Palmas in fulfilling the obligations of Spanish neutrality (as noticed by the French consul) by allowing the escape of seven officers of the Kaiser Wilhelm der Grosse, who were requested to be interned in Spain. ²⁶ Among the surveillance targets were the enemy crews interned in the Canary Islands as a result of the internment of several ships that had been deemed auxiliary to the German Navy.

When the Otavi steamer arrived in Las Palmas in early January 1915 with castaways from ships seized by the Kronprinz Wilhelm, Las Palmas, with 17 ships, and Santa Cruz de Tenerife, with eight, had become the first and fourth Spanish ports, respectively, in the number of German and Austrian ships taking refuge in them. It is necessary to distinguish between the ships that had simply taken refuge after the beginning of the war, which could go to sea if they wanted, and those interned, which had parts of their engines disassembled to immobilize them, since they had violated the rules of neutrality. In Las Palmas, were the German Arucas (interned), Assuan, Duala (interned), ²⁷ Elisabeth Brock, Elkab, Emmi Arp, Illyria, Ingo, Irmfried, Lulu Bohlen, Macedonia (interned), Menes, Otavi (interned), Tenerife and Thekla Bohlen, in addition to the Austrian ships Columbia and Onda. In Santa Cruz de Tenerife were the German Cap Ortegal, Crefeld (interned), Irma Woermann, Kurt Woermann, Prinzregent, Telde, Usambara and Walhalla (interned). ²⁸

After the destruction of the German Squadron of Von Spee in the Battle of the Falkland Islands in December 1914, the arrival of the Otavi at Las Palmas renewed British concerns about the auxiliary cruiser Kronprinz Wilhelm, which still operated in the Atlantic, of which there had been no news since November of the previous year, ²⁹ and which would probably try to take coal from one of the ships in the Canary Islands. Therefore, the Allies still deemed it necessary to continue blockading the Canary ports and practice extreme vigilance to avoid the use of the Canary Islands by Germany, a need that had also been expressed by Leopoldo Romeo, deputy for the islands, in Foreign Office circles. ³⁰ The British also had instruments of economic domination in the islands, especially the supply of coal, to blockade ships of enemy forces taking refuge in Canary ports, such as the Austrian steamers Onda and Columbia in Las Palmas and the German steamers Prinzregent and Usambara in Tenerife. Both in Las Palmas and in Tenerife, British warehouses refused to supply coal to these ships, including that necessary for their own use and internal operations in port, despite the protests of the Austro-Hungarian and German embassies to the Minister of State. ³¹

The Canary Islands were also present in the second stage of activity of the German auxiliary cruisers, which began in late 1915, when the German auxiliary cruiser Moewe began operating on the commercial route that went from the Canary Islands to Cape Finisterre. Among the prizes of the auxiliary cruiser were the Appam and the Westburn, which transported crews of ships sunk by the German auxiliary cruiser. The first was captured by the Canary Islands; the second arrived at Tenerife in February 1916 under the German flag, and in Tenerife it was sunk shortly after its departure from the port of Santa Cruz to avoid being captured by the British cruiser Sutlej, which was waiting for its chance to capture it once it was out of Spanish waters. ³²

Coinciding with these facts, the Allies renewed their requests for the Canary Islands to avoid assisting German ships. According to reports by the British ambassador, in the islands’ ports the German ships had been armed and secretly provisioned to escape, particularly in Tenerife, according to another communication on the preparations of the German ships to sail, made by the French Embassy. ³³ This embassy also denounced at the beginning of March the establishment of a German radiotelegraph station in the tower of the iglesia de la Concepción (Church of the Immaculate Conception), in Santa Cruz de Tenerife, but in the inspections no trace of such station could be found. ³⁴

The Foreign Office was suspicious of the activity on board some ships, such as the German Cap Ortegal, for which it believed that the Deutsches Kohlen Depôt of Santa Cruz de Tenerife had 7,500 to 9,000 tons of coal reserved. ³⁵ The French information also included a possible supply of coal to German ships interned in Tenerife. ³⁶ A letter from Hardinge reiterated his suspicion that German ships intended to leave shortly, perhaps to attack the Madeira Islands, ³⁷ although neither in Santa Cruz de Tenerife nor in Las Palmas were there indications that the German ships had armed and provisioned or tried to escape. ³⁸ This was also believed by the British Consulate in Tenerife, whose night surveillance service, known by the Navy command, had not discovered any suspicious activity. ³⁹ The opinion of consul Croker coincided with that expressed to the civil governor by French Admiral Aubrey, who had visited the islands aboard the cruiser Gloire and had reasons to think that this alarming news about the supply of refugee ships and the attempt to convert them into commerce-raiders were propagated by those interested in stirring panic among merchants and merchant ships, making navigation difficult and making freight rates more expensive. ⁴⁰

Investigations into the suspected clandestine provisioning of German ships in Las Palmas concluded that the accusations were unfounded. ⁴¹ In this sense, the administrator of free ports of Las Palmas believed that these continual accusations, never confirmed, could only have their origin in the excessive zeal of the subordinate agents at the service of the complainants, although Spanish neutrality would be depressed. ⁴² Far from facilitating German actions, the Spanish were more than willing to accommodate the Allied demands.

This Spanish disposition towards the Allies was occasionally recognized by Croker. Commenting on the unsatisfactory lack of action by the captain of the port when the Westburn was sunk, the consul confidentially told the Secretary of State for Foreign Affairs that, apart from that lack of action, he had no reason to complain about the authorities of Tenerife; on the contrary, he had found them generally very willing to assist him and the British cause in whatever way possible, without having observed a willingness to favour the enemy. Croker also expressed his belief that the alarming rumours that had spread from time to time were unfounded and originated, in his opinion, by the Germans themselves in order to interfere with and frustrate trade, from which they were excluded for the time being. ⁴³

On the other hand, besides the surveillance of enemy ships in Canary ports, the British Embassy requested other complementary surveillance measures from the Spanish authorities. Among them was passport control in Las Palmas for people bound to Germany, some of whom were suspected of being reservists. ⁴⁴ In addition, a report from the French Consulate in Las Palmas reported the flight of more than half of the officers and sailors of the German ships Duala, Arucas, Otavi and Walhalla interned in that port, which the consulate attributed to indulgence and lack of surveillance of the authorities, which needed attention. ⁴⁵ However, to carry out the blockade and control of Canary Islands communications, the Allies ─ especially the British ─ relied mainly on their own means and actions to prevent the islands from serving the German Reich in any way.

Cruisers against commerce-raiders

As the commercial routes of the South Atlantic, essential for the supply of Britain, represented a ripe hunting ground for German commerce-raiders, and the crossing of routes in the Canary Islands stood out among the places that were considered most productive for such predators, the British confronted this danger by stationing their cruisers in these shipping lanes. This protective work was not only undertaken by British naval forces, but also by British merchant ships equipped with radiotelegraphy.

There were various means available to the British to directly monitor the area. At the beginning of August 1914, on the Finisterre station, from the Channel to Finisterre and from the Galician coast to Madeira, British trade with French, Spanish and Portuguese ports, together with the European terminals of the trade routes of the East, the Cape and South America, was the responsibility of Rear-Admiral De Robeck, commander of the Ninth Cruiser Squadron (Cruiser Force ‘I’), formed by the ships Europa, Amphitrite, Argonaut, Vindictive, Highflyer and Challenger. The Cape Verde-Canarias station, the southernmost extension of the routes of South America and Africa, was protected by Rear-Admiral Stoddart and the Fifth Cruiser Squadron (Cruiser Force ‘D’), comprising Carnarvon, Cornwall, Cumberland and Monmouth. Even before the beginning of hostilities, the Ninth and Fifth Cruiser Squadrons patrolled commercial routes to Finisterre and the Canary Islands to warn British merchant vessels that war was imminent. ⁴⁶

On 3 August, Stoddart received orders to follow the trade routes, as here was a rumour that two German cruisers ─ the light cruiser Berlin and the gunboat Panther ─ were in the vicinity of the Canary Islands. The news hindered measures to protect British trade in the first days of the war, as well as alarming the French government, which was concerned about the transport of active units from Morocco and French West Africa scheduled for the beginning of August. ⁴⁷ The British rear-admiral arrived on 8 August in Las Palmas with Carnarvon and Cumberland after a search in Canary waters, having found that all the rumours of German cruisers and bases were false; not a single British ship had been disturbed, and German trade had ceased all together. ⁴⁸ On 14 August, Stoddart managed to finalize and place his squadron at the Cape Verde-Canarias station, which released the French merchant ships immobilized on the islands and authorized to leave. ⁴⁹

Soon, however, British trade in the Atlantic was threatened. On 15 and 16 August, the Kaiser Wilhelm der Grosse captured the British ships Galician, Kaipara, Arlanza and Nyanga to the southwest of the Canary Islands. Because they had passengers, the Galician and Arlanza were allowed to continue after their radiotelegraph devices were confiscated. The arrival of the Galician on 16 August at Tenerife revealed the hitherto unknown presence of the commerce-raider. The news was confirmed on the 17th by Arlanza, which communicated with the Cornwall cruiser at Las Palmas. When the Admiralty received news of these captures from Las Palmas, it immediately took measures to reinforce the area. As a first step, Rear-Admiral De Robeck was ordered to deploy the Highflyer and the auxiliary cruiser Marmora to help in the search, along with three other British ships that were crossing the area bound for the Cape and South America. The first results were the capture of two German ships with coal, one of them Professor Woermann, which at the beginning of August had been dispatched from the Canary Islands to a meeting point near the Cape Verde Islands.

On 24 August, the British consul in Las Palmas reported that on the 17th, the Kaiser Wilhelm der Grosse had entered the Spanish colony of Río de Oro, some 300 miles south of Gran Canaria. The Highflyer headed there, discovering on 26 August the German auxiliary cruiser, along with the steamers that had left the Canary Etappen to supply it, such as the Arucas; its departure from Las Palmas had instilled suspicion and alarm among the Allied consuls. ⁵⁰ After a short but intense campaign around the Canary Islands, the Kaiser Wilhelm der Grosse rejected a request to surrender and was sunk by the Highflyer, which barely suffered material damage. ⁵¹ When the Spanish government protested, the British Admiralty justified the action by the absence of an authority in Rio de Oro to ensure the application of international laws regarding neutrals. Thus, in addition to testing the effectiveness of British naval forces, which had destroyed the auxiliary cruiser ten days after starting operations, the Highflyer also tested how British cruisers could interpret neutrality in certain conditions.

The entry onto the scene of the Kaiser Wilhelm der Grosse accentuated the need to monitor the islands, which could be used as bases by German colliers. The Fifth Cruiser Squadron was reinforced by the Canopus, which left Gibraltar on 29 August to join the Carnarvon at Gran Canaria. ⁵² On 8 September, the Victorian auxiliary cruiser visited Santa Cruz de Tenerife and received information about the arrival the day before of the Norwegian Nepos, which was considered very suspicious for having a coal cargo and a German purser, and it was expected to leave at any time. According to the subsequent verification by the British, the Nepos had left Philadelphia for Monrovia (Liberia); from there it had gone to Río de Oro and, finding the Kaiser Wilhelm der Grosse sunk ─ for which its coal load was destined ─ went to Santa Cruz de Tenerife. After the arrival of the Nepos to Santa Cruz de Tenerife, from 8 to 18 September, the Carnarvon and the Victorian and Empress of Britain auxiliary cruisers closely monitored the German ships and the Nepos day and night, since several reports had been received regarding the intention of some of them to escape, though no attempt was made.

At the end of September, another Norwegian ship, the Mowinckel, arrived in Santa Cruz de Tenerife, also carrying coal and a German purser. Likewise, since the end of that month, a closed blockade of the port of Santa Cruz de Tenerife was enforced to prevent the departure of Telde, which ─ following orders from Madrid ─ had been given clearance to depart for Antofagasta under the German promise that its voyage was purely commercial, despite the consular protest that at first had obliged the governor to order it to be interned provisionally.

The blockade remained in place in Las Palmas and Santa Cruz de Tenerife until 9 October. In the middle of that month, as Highflyer and Marmora were sailing south, while the Victorian was coaling in Gibraltar, there was a lack of British cruisers in the Canary Islands. This situation was exploited by Walhalla, which escaped on 21 October from Las Palmas to Santa Cruz de Tenerife. This would strengthen the rumour that circulated during the absence of British cruisers of the possible presence of a German cruiser ─ probably the Karlsruhe ─ in the vicinity of the Canary Islands, where a German collier would be waiting to supply it. ⁵³ The Walhalla arrived in Santa Cruz de Tenerife three hours before the Victorian returned. Additionally, during its absence, the Macedonia entered La Palma on 17 October, to find the German sailing ship Pamir, loaded with nitrates from South America, which had arrived on 1 October ignorant of the beginning of the war. Subsequently, guarded by the Spanish cruiser Catalonia, Macedonia was transferred for security reasons to Las Palmas, where it was interned. ⁵⁴

As soon as it returned to the Canary Islands, the Victorian undertook surveillance tasks near the island of El Hierro, where Kaiser Wilhelm der Grosse had acted two months before. ⁵⁵ While it was doing so, on 22 October, the Crefeld arrived in Tenerife, and as it was not immediately interned by the authorities, it increased the number of ships in Santa Cruz that had to be blocked by British cruisers. The situation was alarming, so the Victorian had to ask the Admiralty for assistance in carrying out surveillance of the Canary Islands. Accordingly, De Robeck, of Cruiser Force ‘I’, was ordered to take the islands under his command when he arrived in Amphitrite on 28 October.

On 9 November, Rear-Admiral De Robeck received a telegram from the Admiralty in Madeira, confirming that until he got new orders, he would include the Canary Islands in his station. ⁵⁶ The following day, a report from a French source reached the British naval forces stationed in the waters of the archipelago, assuring them that the Karlsruhe was south of the Canary Islands. The cruisers Amphitrite, Argonaut and Donegal, and the auxiliaries Calgarian and Victorian, formed a patrol that would be responsible for proving the inaccuracy of the French report. ⁵⁷ Additionally, the French cruiser Bruix made several visits to the Canary Islands at the end of 1914, mainly because of the expected transfer of the German fleet from the Pacific to the Atlantic. ⁵⁸

The Cruiser Force ‘I’, in charge of monitoring the Canary Islands since the end of October, undertook the same actions as its predecessor, Cruiser Force ‘D’. These were visiting all the islands, interviewing the authorities, and taking on coal and water supplies (after permits were received from Madrid), communicating with British consuls, boarding suspicious ships, shooting and torpedo practices ⁵⁹ and the usual tasks of blocking and gathering information about the coal and cargoes of ships in port. In this sense, and with reference to the two Norwegian ships in Santa Cruz de Tenerife, at the end of 1914, the British consul informed the captain of the Calgarian that he would talk about the Nepos and John Ludwig Mowinckel with the Norwegian consul, whom he would assure that the ships would not have difficulties if they were unloaded. Croker also undertook to try to get some prominent firms in Santa Cruz de Tenerife to buy their cargoes, composed mainly of coal, about which he would inform the captain of the Calgarian. ⁶⁰ Indeed, on 3 January 1915, the British consul in Tenerife informed the captain of the Victorian that the two Norwegian ships were discharging at the German dock and that the Dutch ship Alwina, also with coal destined for German cruisers, had already unloaded, while the three German pursers of these ships remained in Santa Cruz de Tenerife. ⁶¹

The unloading of coal from the two Norwegian steamers and the purchase of most of it by the British clearly shows the nature of the relationship of forces in the Canary Islands and the extent to which the Allied blockade and the vigilance of the British cruisers were effective. However, there would be no opportunity to relax, because the day after that consular information was received, on 4 January 1915, Rear-Admiral De Robeck received a telegram in the Argonaut from Gibraltar advising him that the German steamer Otavi had arrived in Las Palmas with crews from ships sunk by the Kronprinz Wilhelm. As a result of this communication, the Argonaut cruiser and the Victorian auxiliary sailed again to Las Palmas. Upon his arrival, in the conversation that De Robeck had with the British vice-consul on 5 January, the latter informed him that the Woermann Linie kept in its warehouse 1,500 tons of coal that it would not yield to any merchant steamer. Thus, the rear-admiral deduced that the coal was being kept ready for a German cruiser in the event that one arrived at the port of Las Palmas. ⁶²

In addition, on 8 January, a message from the Admiralty warned that the auxiliary cruiser Kronprinz Wilhelm would probably try to take on coal from Macedonia, which supposedly was interned but which could escape from Las Palmas, as well as Arucas, if it so desired. This warning led the consul in Las Palmas to establish around-the-clock surveillance of both ships, agreeing to a system of signals to inform cruisers if any of them tried to leave port. ⁶³ However, with the German squadron already destroyed in the Battle of the Falkland Islands, in the first weeks of 1915 the almost permanent presence of British cruisers in the Canary Islands began to decline. In February 1915, the Minister of State told the Spanish ambassador in Berlin that the British warships were already far from the Canary archipelago. ⁶⁴

Finally, the Macedonia left clandestinely at dawn on 15 March 1915 to meet with the German auxiliary cruiser. The British and French ambassadors immediately protested the negligence of the authorities in Las Palmas. ⁶⁵ The escape of Macedonia and the German plans for Arucas, again enlisted to sail ─ although the Navy authorities had removed some parts of its machinery ─ indicated the accuracy of the information that the Admiralty possessed and its control of German communications. In addition, the seizure of the Macedonia by a British cruiser a few days later showed that, despite the reduced presence of British cruisers in the Canary Islands, the blockade remained effective. ⁶⁶ In fact, at the time of the escape of Macedonia, the Finisterre-Canary Islands Division, based in Gibraltar, comprised the cruisers Europa, Amphitrite and Argonaut and the auxiliary cruisers Calgarian and Carmania, ⁶⁷ which continued to monitor enemy ships interned and refuged in the archipelago. ⁶⁸

A few days later, the German sailing ship Pamir, which had taken refuge in Santa Cruz de La Palma since the beginning of October 1914, left the port on the morning of 20 March. The French agent on that island immediately telegraphed to the French Consulate in Las Palmas, which that same day informed the British cruiser in the port. It was believed that the Pamir could try to go to the ports of Bilbao or Gijón, but the sailing ship returned to Santa Cruz de La Palma on 29 March, undoubtedly due to the risk of being caught by one of the British cruisers, whose presence in the area was an obvious deterrent. ⁶⁹

The capture of the Macedonia terminated the operations of the Kronprinz Wilhelm, whose internment in a neutral port brought to an end the first phase of German cruiser activity in the Atlantic, and with it the most intensive stage of the British blockade. The intensity of the blockade was confirmed by the continuous entry and exit of British cruisers in Canary ports. These movements even made it difficult at times to calculate the 24 hours that they could remain in port, as happened with the auxiliary cruiser Victorian, which at the end of October 1914 had always remained in sight of the port of Las Palmas. ⁷⁰

The British cruisers did not disappear, however. In July 1915, the cruisers Argonaut and Essex, and the auxiliary Marmora, were still patrolling the Canary Islands, the first visiting the naval, military and civil authorities of Las Palmas, whose government delegate did not seem to favour the British. ⁷¹ Until the end of that year, they continued to visit both the central and peripheral islands. Thus, in September and December 1915, two communications from the military command of Lanzarote informed the general captain of the Canary Islands about the anchoring of British cruisers in the El Río Strait between the islands of Lanzarote and La Graciosa; ⁷² the British considered that this strait was the only safe natural port in the archipelago for large vessels. ⁷³

At the beginning of 1916, when the second phase of German auxiliary cruiser activity began, the area of Madeira and the Canary Islands was occupied by the British cruisers King Alfred, flagship of Rear-Admiral Moore, and Essex, as well as by the auxiliary cruisers Carmania and Ophir. Moore had taken command of the Ninth Cruiser Squadron a year earlier, replacing De Robeck, who had demonstrated great authority, especially in the Canary Islands, and who on 22 January 1915 was given a new post as second in command of the force that was going to carry out the naval attack in the Dardanelles. ⁷⁴

On 15 January 1916, after sinking the Ariadne, the auxiliary cruiser Moewe captured the British Appam to the north of the Canary Islands, while the King Alfred was near Madeira, and the Essex was patrolling in the islands. The Moewe took advantage of the gap between the two cruisers to continue on its way, sinking the British Clan Mactavish in the vicinity of the archipelago. ⁷⁵ The ocean liner Appam, under the German flag and carrying prisoners from several steamships sunk by the Moewe, reached the North American coast in early February. Then, the French Third Light Squadron, formed by the cruisers Gueydon, Dupetit Thouars, Chateau Renault and Gloire, under the command of Admiral Aubrey, received the order to go to the Canary Islands to attend the British cruisers, while the squadron of Rear-Admiral Moore was reinforced by the armoured cruiser Sutlej. ⁷⁶

Despite the presence of these Allied cruisers, on 22 February the British steamer Westburn, with the German flag raised, as a war prize of the Moewe, reached Santa Cruz de Tenerife. The Sutlej, anchored in the port, could not intercept Westburn before entering Spanish waters, ⁷⁷ nor could it prevent its sinking within the same waters.

It seemed necessary, then, to re-establish close naval surveillance of the Canary ports, at a time when reports had arrived of the supposed escape of German ships. ⁷⁸ Although the surveillance service of the British Consulate in Santa Cruz de Tenerife had not discovered anything suspicious, and although Croker agreed with the French Admiral Aubrey in believing that such reports were propagated by those interested in hindering navigation and increasing freight rates, the truth was that in the following months there was greater vigilance by the British Ninth Squadron, assisted by the French Third Light Squadron. ⁷⁹ In addition, their operations were facilitated from March 1916 by the entry of Portugal into the war against Germany, which allowed cruisers to make unlimited use of the ports of Funchal and Cape Verde. ⁸⁰

British cruisers maintained an assiduous presence in the Canary Islands. Proof of this was the great alarm in Santa Cruz de Tenerife caused by the British cruiser Sutlej, which after anchoring in the port, on the afternoon of 23 April 1916, accidentally fired a cannon shot that fell loudly, but harmlessly, near the town. Immediately, from the Sutlej, an officer landed who, in the company of the British consul, presented in the name of his commander his apologies to the civil governor, to whom he assured that those responsible for such oversight had been severely punished for projecting a shot that could have caused much damage. ⁸¹ The British Embassy strongly regretted this unfortunate event in a letter addressed to the President of the Council of Ministers, the Count of Romanones, on 27 April, ⁸² who answered to the British representation that he did not doubt that necessary measures had been taken by the British Navy to prevent such accidents from happening again. ⁸³

A few days after this event, another notable British action took place in Canary waters. The German steamer Telde, a refugee in Santa Cruz de Tenerife, had been moved towards the inland port, but the strong winds of 2 May dragged the ship out to sea at night, and during the early morning of 3 May was helped by a tug from the Navy command. However, while the Telde was being towed to port, at dawn that day, the British cruiser Essex ─ that from Dakar had received a strictly reserved message sent from Tenerife by consul Croker ⁸⁴ ─ approached at full steam, fired a warning shot, launched a boat and declared the entire crew of Telde prisoners of war, which was approximately 10 miles from the port when it was captured by the British cruiser. ⁸⁵ The cruiser ordered the tug to return to land, without paying attention to the protest against the illegal capture of the ship, which, according to its captain, had been captured in Santa Cruz by the Essex within territorial waters. ⁸⁶ The truth, however, was that by provisionally putting into effect the XIII Hague Convention on the rights and duties of neutrals in maritime war, Spain had set in November 1914 a zone of Spanish jurisdiction limited to three nautical miles, as it had communicated to foreign governments. ⁸⁷

The capture of the Telde, which was led by the Essex to San Vicente (Cape Verde), demonstrated the effectiveness of the still-active surveillance carried out in the Canary Islands by the Ninth Cruiser Squadron. This unit was commanded since 22 September 1916 by Rear-Admiral Fremantle, Moore’s successor, who until the end of that year was busy establishing the measures to be taken against possible commerce-raider attacks, especially near the Canary Islands if, as expected, German auxiliary cruisers hindered trade again (in November of that year the Moewe began its second voyage). Furthermore, these German auxiliary cruisers had the added purpose of facilitating the intensification of submarine warfare at the end of 1916. ⁸⁸ Thus, until the end of 1916, British warships were still patrolling, while French warships from the West African coast occasionally collaborated with the former in the surveillance of the Canary Islands. ⁸⁹

Conclusions

If indeed, once the war began, the commercial routes of the South Atlantic suffered from the actions of the German auxiliary cruisers, whose objective was to hinder supplies destined for the United Kingdom, the British were thoroughly engaged from the very beginning of the war in preventing those actions, trying to cut off the coal supplies that German cruisers could receive, restricting their telegraphic communications, and ultimately pursuing and sinking them, or forcing their entry into a neutral port.

In the recently begun German cruiser war, it was considered necessary that the first blows be delivered as quickly as possible, with isolated operations executed at the same time, to make the cruiser war more sensitive on many different points, creating panic and making shipping costs more expensive. From the Etappen – supply areas established in neutral countries – to the fixed meeting points, the fastest available steamers were sent in large numbers, such as auxiliary ships, companion ships and colliers, with the mission of providing the cruisers what they needed to conduct the war on trade in the Atlantic. Within these trade routes of the South Atlantic, its busiest junctions presented the most opportunities for the operations of German cruisers, among them the crossing of routes that took place in the Canary Islands, with ports of first order and among the first of the eastern Atlantic. Therefore, the German war of cruisers around the Canary Islands would ensure, on the one hand, the presence of enemy merchant ships and, on the other hand, the assistance of some of the numerous German merchant ships that were in their ports, especially as colliers. That was the case of the Arucas, the Walhalla and the Macedonia, which served the Kaiser Wilhelm der Grosse and the Kronprinz Wilhelm, or were enlisted to take advantage of any opportunity to supply the cruisers. It was not by chance, therefore, that the beginning and end of the operations of both auxiliary cruisers were linked to the Canary Etappen.

Those possibilities in the archipelago for the German cruiser war motivated the immediate Allied action to block the ports and control communications in the Canary Islands, at all costs preventing the islands from serving in the provisioning of, and transmission of news to, the German cruisers. To do this, the Allies used three very effective means at different levels, which rested on the undisputed British hegemony in the archipelago. First, at the economic level, Britain controlled the main infrastructures and port and communication services. In addition, the Canary import and export economy depended on British shipping and markets. Thus, a community of very close interests had been created between the large British colony and the most active elements of Canarian society. It was therefore enough for the British to activate their network of influence and their control over these infrastructures to prohibit supplies to the enemy or to establish close surveillance over all German activities on the islands. The result was that the Austrian steamers Onda and Columbia in Las Palmas, and the German steamers Prinzregent and Usambara in Tenerife, could not even get the coal they needed for their internal operations, as the British refused to supply it; or the established night-time surveillance in the ports.

Second, beyond their own vigilance, at the diplomatic level, the British and French stimulated, jointly through permanent pressure from consuls and ambassadors, the surveillance that they believed should be exercised by the Spanish authorities and, above all, the decision-making that corresponded to those authorities. These could not be foreign to the influence of Britain, taking into account its economic hegemony and its extensive and well-established network of contacts and influences. This was how they managed to disable the radiotelegraph stations of the German merchant ships operating in the Canary ports from the first week of August 1914, which since then could not send any information to the German cruisers. The result of that diplomatic pressure was also the internment, although with less speed than they thought the war context demanded, of the ships Walhalla and Crefeld, which had provided services as auxiliary ships – colliers, companion and transport ships – of these cruisers.

Third, at the strategic and naval level, British primacy was even more decisive, since the security of the archipelago ultimately depended on British naval forces, and on its clear superiority could be derived the most forceful actions to avoid any service of the Canary Etappen to the German commerce-raiders. The British had many means to counteract potential German actions at the crossroads of the Canary Islands, since to the primacy of the Royal Navy was added that of its merchant fleet, so that it could also count on the participation of merchant ships in the efforts of British cruisers to protect trade. It was one of those merchant ships that, despite having its radio equipment destroyed, reported the first news of the existence of a German commerce-raider – the Kaiser Wilhelm der Grosse – in the vicinity of the Canary Islands.

In short, beyond their control of the islands’ infrastructures and Allied diplomatic pressure on the Spanish authorities, we have seen how, to resolve those concerns that had been the subject of diplomatic pressure, the British finally relied mainly on their own means and actions: the almost permanent presence of the cruisers that, occasionally assisted by some French units, carried out direct surveillance, which in the Canary Islands area was done mainly by the Ninth Cruiser Squadron. If the German steamship Telde had been the object of diplomatic action, it was a cruiser of the Ninth Squadron that ended up catching it on the outskirts of Tenerife.

Thanks to this close monitoring of the Canary Islands, the Highflyer managed to destroy the Kaiser Wilhelm der Grosse after an intense but short campaign around the islands. In its actions, the commerce-raider had provisioned at a previously determined meeting point near the island of El Hierro; and after its destruction, British cruisers continued to monitor those waters to prevent other cruisers from being supplied. The maintenance of surveillance also had discouraging effects, as proved by the frustrated escape of the Walhalla or the forced sale to the British deposits of the coal that the Norwegian steamers possessed, which was originally destined for the Germans.

Finally, Britain managed to keep the Atlantic trade routes clear, fighting the threat posed by the actions of German commerce-raiders near the Canary Islands. Those which were not destroyed would be tirelessly persecuted by the cruisers, and when one of the colliers defied its blockade of the ports – as did the Macedonia – it would end up being captured, forcing the end of the operations of the Kronprinz Wilhelm, the last of the German auxiliary cruisers that still operated in the Atlantic in March 1915. In this cat-and-mouse game in the central eastern Atlantic, the German gamble was phenomenal, but sooner rather than later the British Admiralty managed to impose the real balance of these two opposing forces. The result for the Canary Islands was that their waters and ports remained open to navigation, although their traffic was progressively and inexorably decreasing as a result of the new needs of the war economy. At the end of 1916, Fremantle, then in command of the Ninth Cruiser Squadron, had instructions to adopt special precautions in the event that German submarines attacked his area around the Canary Islands, and effectively the submarine campaign would intensify at the end of 1916 and would directly affect the Canary archipelago, posing new challenges in the economic war. ⁹⁰