C-4 was a of the Spanish Navy commissioned in 1929. She served initially under the Kingdom of Spain, then as a unit of the Spanish Republican Navy under the Second Spanish Republic. She took part in the Spanish Civil War on the side of the Republican faction loyal to the government of the Second Spanish Republic. After the war, she became part of the naval forces of Francoist Spain. She was sunk in a collision in 1946.
Design
Construction and commissioning In 1915, the Spanish Cortes Generales passed the Miranda Law, a naval construction program which called for a Spanish Navy force that included 28 submarines. Shortages during World War I (1914–1918) and budgetary limitations led to delays in the program, but a new naval law passed on 1922 authorized the construction of the six s. The Sociedad Española de Construcción Naval (SECN) built all six of the submarines at Cartagena, Spain.
C-4 was the fourth of the class. SECN laid her keel on 1924 and launched her on 1929. She was commissioned on 1929.
Service history
Kingdom of Spain, 1929–1931 Upon commissioning, C-4 was assigned to the submarine squadron at Cartagena. She and her sister ships C-1, , and took part in fleet maneuvers in the Mediterranean Sea during September and October 1929. In mid-August 1930, all six C-class submarines — the last two vessels of the class, and , having joined the fleet during 1930 — arrived at Ferrol from Cartagena and then participated in maneuvers in the Cantabrian Sea along the northern coast of Spain during September and October 1930.
Second Spanish Republic, 1931–1936
On 14 April 1931, the Second Spanish Republic was proclaimed, replacing the Kingdom of Spain. The Spanish Navy came under the republic's control as the Spanish Republican Navy.
In June 1933, maneuvers began in which C-4, C-2, C-3, C-5, C-6, the submarines and , four cruisers, nine destroyers, the seaplane carrier , and several smaller vessels participated. They concluded on 1933.) Also in 1933, C-4, Isaac Peral (the former C-1), C-3, C-5, B-5, and the submarine conducted maneuvers off Tarragona. They arrived at Castellón on 1933 at the end of a voyage from Vinaròs, then got back underway to continue their training cruise, which lasted until the end of October 1933. All six C-class submarines took part in fleet maneuvers during May and June 1934.
On 29 July 1935, the six C-class submarines departed Cartagena to begin a lengthy training cruise. They called at Melilla on the coast of North Africa from to and at Cádiz from . They then set course for the United Kingdom, reaching Plymouth, England, in mid-August. They subsequently visited Brest in France, Ferrol, and the Canary Islands before proceeding to West Africa, where they called at Dakar in Senegal and Villa Cisneros in Río de Oro. They then returned to the Canary Islands for a stop at Las Palmas on Gran Canaria and called at Larache in Spanish Morocco before concluding the cruise with their arrival at Cartagena in September 1935.
C-4 was one of several submarines that took part in maneuvers in the Canary Islands during the first half of May 1936. She returned to Cartagena upon their completion.
Spanish Civil War, 1936–1939 On 17 July 1936, the Spanish Civil War began, with Nationalist forces under Francisco Franco opposing Republican forces which remained loyal to the Second Spanish Republic. At the time, C-4 was at Cartagena as a unit of the Cartagena division. Early on , the division received orders from the Republican government to patrol the Mediterranean along the Andalusian coast between Cabo de Gata and the Strait of Gibraltar to intercept ships carrying Nationalist troops and equipment from North Africa to Spain. C-4, Isaac Peral, C-4, and C-6 got underway immediately, rendezvoused at sea with the submarine , and began the patrol.
It quickly became apparent that most of the division's officers supported the Nationalists while the crews supported the Republicans, so the crews mutinied and placed most of the officers under arrest. Only two days into the operation, on 20 July, the submarine division entered the harbor at Málaga, where the division's commander, (Frigate Captain) Francisco Guimerá Bosch, and most of the other senior officers in the division — including C-4′s commanding officer. — were relieved of command and imprisoned on the prison ship Monte Toro. Only the commanding officer of Isaac Peral retained his command. Isaac Peral′s former executive officer took command of C-4, and C-4′s former commanding officer later was executed.
C-4 soon resumed the patrol off Andalusia. She saw her first combat action of the war on the night of 26–27 July 1936, when she attacked two merchant ships crossing the Strait of Gibraltar, firing a torpedo and 37 rounds from her deck gun without scoring a hit. Subsequently, she received orders to proceed to Spain's northern coast, but Nationalist coastal artillery damaged her while she was off Huelva. Aborting her voyage to northern Spain, she made port at Tangier on the coast of North Africa. She then proceeded to Málaga to transfer her torpedoes and ammunition to C-3, then proceeded to Cartagena, where she spent about 20 days while undergoing repairs.
After the completion of her repairs, C-4 got underway from Cartagena in company with C-5 on 1936 bound for Málaga, which the submarines reached on . C-4, C-3, and C-5 departed Málaga on bound for the Bilbao carrying a large quantity of weapons and ammunition for Republican forces fighting in northern Spain. They arrived at Bilbao on and unloaded their cargo. She conducted patrols from Bilbao, but had no successes. On 1936 they put back to sea and set course for Málaga, which C-4 and C-3 reached on .
C-4 arrived at Málaga on 1936 and conducted patrols in the Alboran Sea from there until the end of 1936. At the beginning of 1937, she shifted her base to Valencia and began patrols off Spain's Levante coast. On 1937 C-4 and Isaac Peral departed Cartagena to intercept troopships bringing troops of the Italian Corpo Truppe Volontarie (Corps of Volunteer Troops) to Spain from Fascist Italy, which actively supported the Nationalist faction. The submarines had no success, and they returned to Cartagena early in April 1937. On 1937, the two submarines got back underway with orders to deploy to the northern coast of Spain, but Isaac Peral suffered a mechanical breakdown in her diesel engines as the submarines neared the Strait of Gibraltar, forcing her to return to Cartagena. C-4 aborted her voyage to northern Spain to escort Isaac Peral back to Cartagena.
At the end of April 1937, C-4 again departed for the northern coast of Spain. On 1937, she arrived at Bilbao, where she rendezvoused with C-2 and C-6. When Bilbao fell to Nationalist forces, C-4 and C-6 moved first to Santander and then to the Port of El Musel at Gijón. While at sea onn 1937, C-4 sighted the Nationalist light cruiser . C-4 was unable to make an attack and was driven off by a depth charges. She withdrew and returned to Santander.
When the fall of Santander to Nationalist forces became imminent, C-4 embarked Republican military officers and politicians requiring evacuation and moved from Santander to Gijón on 1937. She rendezvoused with C-2 and C-6 at Gijón. Nationalist ships bombarded the Port of El Musel on 1937, and C-4 sustained damage from numerous shrapnel hits. The bombardment prompted C-4 and C-2 to flee to France that day, where C-4 anchored at Le Verdon-sur-Mer on without permission from Republican authorities and C-2 moored at Brest. During their stay in France, the commanding officers of the two submarines defected to the Nationalists and conspired to seize control of either C-2 alone or both submarines — according to different sources — in collaboration with Nationalist agents and place them under Nationalist control, but the attempt failed and they were relieved of command.
The Soviet Union supported the Republicans, and a Soviet Navy officer took command of C-4 on 1937. C-4 underwent repairs in France, and after their completion departed Bordeaux on 1938 and headed for Cartagena, which she reached on . There a different Soviet Navy officer took command of her, and — after post-repair trials and preparations to return to combat — on 1938 she departed Cartagena and proceeded to Barcelona, where she arrived on Based at Barcelona, she conducted several patrols along the coast of Catalonia. She headed for Mahón on Menorca in the Balearic Islands on 1938, then returned to Barcelona on . She again got underway from Barcelona on 1938 to escort an approaching merchant ship into port.
Republican-held Menorca in the Balearic Islands was under blockade by Nationalist naval forces, but Republican submarines found they could rather easily run the blockade. C-4 departed Barcelona on 1938 to deliver mail to Mahón on Menorca, then returned to Barcelona on , becoming the first submarine in history to transport mail between Barcelona and Mahón. Following that, she proceeded to Cartagena, where she arrived on 1938; one source claims that she completed her second and final mail run to Mahón by that date. C-4 got underway from Cartagena on 1938 in company with C-2, and the two submarines patrolled in the Cape Palos area off Cartagena until September 1938.
C-4 entered drydock for repairs at Cartagena on 1938. She began post-repair sea trials on 1938, but ran aground. Due to several complaints about the incompetence of her Soviet commanding officer, a Spanish officer relieved him of command on 1938. She had suffered additional damage and underwent further repairs at Cartagena Naval Base. Once again seaworthy, she began a patrol between Barcelona and Cape Tortosa on 1939, completing it with her return to Cartagena on . Over the next few weeks, she made only a few sorties, and none lasting more than a few hours.
With the Nationalists close to victory in the civil war, C-4 was part of a Spanish Republican Navy squadron that fled Cartagena on the morning of 1939 to seek refuge at Bizerte in Tunisia, which it reached on . The Republican ships remained there through the end of the war on 1939.
Francoist Spain, 1939–1946 At the beginning of April 1939, representatives of the victorious Nationalists arrived at Bizerte to take possession of the Spanish ships there. With a new commanding officer and crew, C-4 departed Bizerte with the rest of the squadron on 1939 and arrived at Cádiz on .
C-4 subsequently was part of the naval forces of Francoist Spain, which put her in full commission on 1939. However, the economic hardship Spain faced in the aftermath of its civil war combined with the outbreak in September 1939 of World War II — although Spain remained neutral in the conflict — made naval operations difficult for Spanish forces. As a result, C-4 spent most of the World War II years in port.
The conclusion of World War II in 1945 allowed C-4 to resume active operations. With Caudillo of Spain Francisco Franco aboard, she took part in a ceremony on 1946 in honor of the 1,476 Nationalist troops killed aboard the steamer during the Cartagena uprising in 1939.