Pre-War
The first submarine built in Germany was the two man submarine Brandtaucher, which sank to the bottom of Kiel harbor during its first test dive. The vessel was designed in 1850 by the inventor and engineer Wilhelm Bauer and built by Schweffel & Howaldt in Kiel for the Imperial German Navy. Brandtaucher was later rediscovered during dredging operations in 1887, and subsequently raised sixteen years later and placed in a museum in Germany, where it remains today.
This was followed in 1890 by W1 and W2, built to a Nordenfelt design. In 1903, Germaniawerft dockyard in Kiel completed Germany's first fully functional submarine, Forelle which was sold to Russia during the Russo-Japanese War in April 1904. The first works were carried out by the Spanish engineer Raymondo Lorenzo d'Equevilley Montjustin (submarine Narval), who based the German Navy's first U-boat design, U-1 on the Russian export models bound for the Russo-Japanese War. U-1 was commissioned into the Imperial German Navy on 14 December 1906. This was based on the Karp-class which had a double hull, was powered by a Körting kerosene engine and armed with a single torpedo tube. It was designated U-1, with the 50% larger U-2 design having two tubes. A diesel engine was not installed in a German Navy boat until the U-19-class of 1912–13. At the start of World War I, Germany had 48 submarines of 13 classes in service or under construction. Germany's first U-boat, U-1, was retired in 1919, and is currently on display at the Deutsches Museum in Munich.
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