Shortly after the foundation of the new Turkish Republic, the efforts were on the way to buy submarines for the navy. Officers were sent to France, the Netherlands and Sweden and the submarines used by the countries were investigated. Although the reports have favoured the Swedish submarines, because of commercial interests, the order of building the submarines were placed to IvS firm in Netherlands.
The Article 191 of the Versailles Treaty prohibited Germany to build or to operate any submarines. Submarine officers and engineers, that wanted to preserve the German know-how about designing, building and operating submarines founded in Netherlands a private company named Ingeenieurkantoor voor Scheepsbouw (IvS). The firm was secretly financed by the German Navy. The submarines designed and built by this firm were the forerunners of the U-boots of the Second World War and were sold to many countries including Turkey. This firm took part almost in every submarine project of Turkey in pre- 2.World War period.
According to this contract, the keel of the first submarine was laid on 28 December 1925 and the keel of the second on 28 January 1926 in Feijenoord shipyard, the Netherlands. On 22 May 1928 the submarines named as TCG 1.İNÖNÜ and TCG 2.İNÖNÜ sailed away from Rotterdam under a Turkish commander but under foreign flag. They were commissioned into the Turkish Navy after their arrival in İstanbul on 9 June 1928. These two submarines conducted their first divings on 25 July 1928 in İstanbul with success.
The naval officers that attended the submarine courses held in Germany and Turkey during the First World War started to teach the new generation of submariners.
In 1929, 4 destroyers and 2 submarines were ordered from Italian shipyards. The TCG SAKARYA, the first of the two, was laid down on 1 February 1930. The Second submarine,TCG DUMLUPINAR was laid down on 15 February 1930. Both were completed in one year. They arrived in İstanbul under the command of a Turkish officer and with Turkish -Italian mixed crew on 5 November 1931. On 6 November 1931 both submarines were commissioned into Turkish Navy.
IvS was also involved in building the E-1 submarine, based on the experimental UG design of 1918, for the Spanish Navy in Cadiz. Engines and parts were manufactures in Germany and Holland for assembly in Spain. E-1 was launched on 22 October 1930. The most successful German submarine commander of 1.World War, Von Arnaud De Laperie was conducting the sea trials of E-1. The almost completed submarine was put on sale after the Spanish Civil War broke out. Von Arnaud De Laperie was teaching at the Turkish Naval Academy. He informed the Turkish Navy about the sale of E-1. A delegation sent to Spain bought the submarine for 9 million pesetas. On 29 December 1936 she was commissioned into Turkish Navy as TCG GÜR.
In 1936, 4 submarines were ordered from Germania Werft in Germany. Two of them were to be build in Germany, and two in Turkey. The contract signed by Deputy Defence Minister General Kazım Özalp for Turkish side and by Ferrostahl A.G and N.V. Ingenieurskantoor Voor Scheepsbouw for German side. According to the contract the workforce used for the building of the submarines had to consist 75 % of Turkish workers. The workforce used for mounting the devices and equipment had to be 30 % of Turkish workers.
The names of the four submarines were given by Atatürk: SALDIRAY, BATIRAY, ATILAY, YILDIRAY.
TCG SALDIRAY and TCG BATIRAY were laid down on 10 February 1937 in Germany. TCG ATILAY was laid down on 14 August 1937 and TCG YILDIRAY on 9 September 1937 in İstanbul.
TCG SALDIRAY was finished first. She was launched on 23 July 1938. And on 2 April 1939 she started her sail under German flag but under the command of a Turkish officer to Turkey. On 5 June 1939 she was commissioned into Turkish Navy.
TCG BATIRAY was launched on 28 September 1938. As the Second World War started, her trails were not completed. The German Navy took her over and named U-A. She sunk during the war 7 ships for a total of 40,706 tons. From August 1942 on she was used as a training submarine. On 3 May 1945 she scuttled herself in Kiel.
TCG ATILAY was launched on 19 May 1939 in İstanbul, 21 months after her keel was laid. She was commissioned in 1940. On 14 July 1942 she was lost all hands off the mouth of Dardanelles after striking a moored mine. This was the first deadly accident of the Turkish submarines. 38 submariners died in TCG ATILAY.
TCG YILDIRAY was launched on 28 August 1939. As the German engineers and technicians left Turkey after the start of the war, she was left unfinished. She was completed during the war with difficulties and commissioned into the navy on 15 January 1946.
In 1939, Turkish government signed a contract with Vickers shipyard for 4 submarines and 4 destroyers. The first three submarines TCG ORUÇREİS, TCG MURATREİS and TCG BURAKREİS were laid down on 24 May 1939. The last one TCG ULUÇALİREİS was laid down on 30 September 1939.
TCG ORUÇREİS was launched on 19 July 1940 and TCG MURATREİS one day later. The ship carrying the crews of these submarines was torpedoed off the coast of Mersin by an unidentified submarine. Therefore, these two submarines sailed to Turkey under British flag and with British crew. TCG ORUÇREİS was commissioned into the navy on 9 May 1942 and TCG MURATREİS on 25 May 1942.
TCG BURAKREİS was leased by the British Navy for the duration of the war after her launching on 19 September 1940. She joined the Royal Navy as P-614 and served until the end of the war. She was commissioned to the Turkish Navy on 19 January 1946.
TCG ULUÇALİREİS was, too leased by the Royal Navy for the duration of the war. Unfortunately she was sunk on 18 April 1943 by German U-Boot U-123 off the African West Coast.