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Seaborne troop movements and massive military imports were critical to both sides in the Spanish Civil War, 193639. This triggered two unique undersea campaigns, each involving foreign submariners. The Republican Submarine Force consisted of 12 boats built in Spain to U.S. designs in the 1920s. They were manned by crews loyal to Madrid’s leftist government, but the officer corps was so decimated by executions and defections that the boats were ultimately commanded by Soviet captains overseen by Spanish political commissars. Franco’s Nationalist submarine force, on the other hand, included 2 submarines transferred from Italy and 4 “Legionary” submarines flying the Spanish flag, but manned by “volunteer” Italian officers and crews. In addition Mussolini secretly ordered other units of his large submarine force to sink neutral ships with cargoes destined for Republican Spain. Outraged neutrals cried “Piracy”, and also organized international naval patrols to combat the anonymous Captain Nemos.

The Naval Situation
The Spanish Fleet remained largely under the control of the Naval Ministry in Madrid, including the battleship JAIME PRIMERO, 3 cruisers, 15 destroyers and 12 submarines. Most naval officers sympathized with the Franco-led revolution, however, creating mistrust and hostility between commissioned and noncommissioned ranks. In view of the uncertain allegiance of the officers, Minister of Marine Jose Giral y Pereira abruptly dismissed them by radio, appointed Chief Engineers to command, and ordered arms distributed to crewmen. A tragedy followed. Of the 764 officers and midshipmen on active service at the outbreak of the revolution, 320 officers were executed by lower deck committees within three months, and 290 more resigned or were expelled. This catastrophe destroyed the effectiveness of the Republican Navy, and gave Minister Giral notoriety as the assassin of the officer corps. The Nationalists soon overran the naval bases at Ferro) and Vigo, where they took over the old battleship ESPANA and the modem cruisers ALMIRANTE CERVERA, CANARIAS and BALEARES. From these circumstances the opposing submarine campaigns developed.

The Republican Submarine Campaign
The oldest submarines in the Spanish Navy were six B-Class boats built at Cartagena in 1921-23 to Electric Boat Company designs. They were 210-foot, 835-ton submarines, somewhat similar to American R-Boats. They were capable of 16 knots on the surface and were armed with four 18-inch bow torpedo tubes and a three inch gun. Manned by a crew of 28 under the command of a Lieutenant, their rust-pitted hulls were not considered safe below a depth of 66 feet.

Six C-Class submarines had also been built at Cartagena in 1928-30 under Electric Boat license. They were 247-foot, 1144-ton boats with a speed of 8.5 knots submerged and had a three-inch gun and four bow and two stem 21-inch torpedo tubes. With an operating radius of 4000 miles and a complement of 40 men under a Lieutenant Commander, they could operate safely down to 270 feet.

In the early morning hours of July 18th the Naval Ministry in Madrid ordered the submarines at Cartagena to load warheads and sail immediately to blockade the port of Melilla, Morocco. Since the Minister of Marine was unsure of the allegiance of the officers, he ordered the boats to report directly to him every four hours. The submarine radiomen had been cleared by Madrid for loyalty to the government, and were told to pass operational orders to lower deck committees to ensure compliance.

Off Melilla the Flotilla Commander disposed his wolfpack on a nine-mile semicircle, with instructions to dive on station at dawn on the 20th. He ordered his captains to intercept the rebel transport MONTE TORO, to ascertain whether she carried troops, and if she resisted to sink her.

The Flotilla’s officers were reluctant to open fire on a Spanish transport, but all submarines were in position by 0900 on July 20th. Conflicting orders then arrived from naval headquarters, instructing the Aotilla to abandon the blockade and recross the Straits to patrol off Malaga, Spain. Commander Bosch requested confirmation of these contradictory orders, but in Madrid senior officers were defecting and the naval staff was clearly in chaos. He therefore continued to blockade Melilla. This decision sparked dissension aboard the submarines, however, as suspicious crewmen argued with the officers about which of the conflicting commands was authentic and should be obeyed. At 1440 Madrid reconfirmed the orders to withdraw northwest to Malaga, and the subs departed. The bungled blockade of Spanish Morocco lost the Republican Submarine Force its one opportunity to contain the revolution, and exposed the wavering allegiance of its commissioned ranks.

Disaster then struck the Spanish Navy from within. On July 21st, 9 officers from four B-Ciass boats were arrested along with 6 submarine base officials; all 15 were then executed for treason. Three weeks later 20 officers from the Cartagena submarines who were incarcerated aboard the prison ship ESPANA No.3 were shot along with 132 other naval officers. These atrocities destroyed the Republican Submarine Force’s leadership, professional competence, morale, discipline, and aggressive spirit.

A grave strategic mistake followed in August when the now decimated Submarine Force was ordered north to show the flag off politically important ports in the Bay of Biscay. Remote from base support in the Bay of Biscay the Republican submarines achieved nothing.

The experience of two Republican submarines are of particular interest:
• C5 departed Cartagena for the Bay of Biscay on August 22, 1936. On the night of August 31st off Cape Mayor she fired a torpedo that hit the 15,700-ton Nationalist battleship ESPANA, but the warhead failed to detonate because of a defective exploder or too large a track angle. Ordered back to the Mediterranean with her sister ships, C-5 vanished with all hands off Ribadesella about December 30th. The cause of her disappearance is unknown, but her captain, Lieutenant Commander Jose Lara y Dorda, is said to have stated his intent to overpower his crew and defect, which may have precipitated C-5’s loss.
• C-6 was dispatched to the Bay of Biscay on August 15, 1936, but the crew arrested the captain and sailed back to Cartagena, where they charged him with failure to attack the ESPANA and CERVERA when the warships were within range. Under a junior officer C-6 again sailed for Biscay on September 1st, but was recaJJed to the Straits on October 2nd. She returned north to the Biscay campaign under Captain Burmistrov of the Soviet Navy, but stiJJ achieved no results. An aircraft bomb put her out of action at Gijon, where she was scuttled on October 20th, 1937.

Obsen,ations on the Republican Submarine Campaign
The Spanish Civil War demonstrated again the critical need for professional competence and leadership in undersea operations. The tragic Joss at the outset of experienced submarine officers destroyed the Spanish Navy’s morale, discipline and offensive spirit, leading to malingering, sabotage and defection. Although ideological fervor ran high in the crews, the failure of the campaign demonstrated that submarines cannot be commanded by committees, nor by unpopular foreigners monitored by political commissars. The absence of high-level direction in Madrid and Cartagena also doomed the Republican submarine campaign. With no consistent strategy against Nationalist warships or supply Jines, submarines were dispatched to areas chosen for political effect where they were employed against unsuitable targets. Without logistic support, and exposed to air raids in unprotected ports, they were put out of action or defected. The net result was 8 submarines lost with over a, hundred men, and no damage to the enemy.

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The Nationalist Submarine Campaign
Concerned over growing military shipments from Moscow, General Franco declared a blockade of Loyalist ports in the Mediterranean and Bay of Biscay, and directed Nationalist warships to intercept cargoes destined for the Republicans.

To carry out the naval blockade Mussolini transferred two ARClllMEDE class submarines to the Nationalist Naval base at Palma. Before their transfer to the Spanish Navy these boats had already carried out three patrols for the Nationalists totalling 48 days at sea. Their names were not stricken from the Italian Naval List but were assigned to two new BRIN class submarines on the ways at Taranto. Mussolini also supplied four Spanish “Legionary” submarines: !RIDE, ONICE, FERRARIS, and GALILEI. He loaned these boats to the Nationalist Navy with a crew of Italian “volunteers” operating under Italian control, and in addition secretly ordered other submarines to attack designated neutral ships carrying cargoes destined for Madrid. While these clandestine boats operated under Italian control, they were instructed to fly a Spanish naval ensign if forced to the surface to give Mussolini deniability for their actions. This unorthodox blockade was not popular with the naval high command in Rome.

The Nationalist submarine antishipping campaign got off to a fast start. Three Republican ships were torpedoed: The Spanish merchant ship CIUDAD de CADIZ was sunk off the Dardanelles, and the Spanish merchant ship AMURO destroyed. Before the end of August, a Spanish steamer was shelled by a submarine off the French coast, a French passenger ship chased into the Dardanelles by a submarine, and the Soviet freighter TUNIY AEV departing Algiers for Port Said was sunk by an Italian “Legionary” submarine.

August ended in an explosion of depth charges after the “Legionary” submarine IRIDE fired a torpedo at the British destroyer HMS HA VOCK on passage in the Western Mediterranean. The torpedo narrowly missed HA VOCK, which then picked up !RIDE on sonar and called other destroyers to the scene. A deliberate depth charge attack followed that shook up IRIDE but failed to put her out of action (HAVOCK got her revenge in October, 1940, by sinking IRIDE’s sister submarine BERILLO off Sidi Barrani). London vigorously protested the attack on HA VOCK, but Rome denied responsibility.

In the first week of September, the British tanker WOODFORD was sunk near Valencia, and the Soviet steamer BLAGAEV sunk by a submarine in the Aegean off Skyros. Moscow claimed that it had “indisputable proof” that Italy was responsible for sinking the TUNIY AEV and BLAGAEV, and broke off relations when Rome denied involvement and the attacks continued.

British and French diplomats, anxious to dissuade Mussolini from forming a closer alliance with Hitler invited Italy to participate in an international conference at Noyen, Switzerland to organize anti-piracy measures.

On September 14, 1937, in the absence of Italy, the Noyen Conference authorized patrolling British and French warships to counterattack submarines or aircraft attacking neutral vessels in international waters. On that day Mussolini secretly called off his undersea campaign except for the four “Legionary” submarines. The Noyen decision in effect restricted Nationalist submarines to attacks within Spanish territorial waters.

Rome decried the Noyen Conference, but, not wishing to be excluded, demanded that Italian warships participate in the anti-piracy patrols. The British agreed, knowing from decoded messages that Italian submarine attacks had now been suspended.

On November 21st a prowling Italian submarine torpedoed the 7975-ton Loyalist cruiser MIGUEL de CERVANTES off Cartagena, putting her out of action for months. At the end of January another British ship was sunk off Valencia by a Nationalist submarine, and on June 15th the British ship DELL WYN was destroyed off Gandia.

A total of 91 Italian warships and submarines participated in the Spanish Civil War, during which Italian “Pirate” submarines are said to have sunk 72,800 tons of shipping without suffering any losses. Audacious covert operations by clandestine submarines with “volunteer” crews on loan from a neutral power proved highly effective in the Spanish Civil War. Similar undersea guerilla warfare based upon the covert nature of submarine warfare could well be repeated in a future naval conflict.

Tom Paine

[The above article is digested from “Chapter I 0 – Spanish Submarines” of Tom Paine’s annotated submarine bibliography] .

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