The Type UB III submarine was a class of U-boat built during World War I by the German Imperial Navy.
The Type UE II submarines were a class of submarines built by the German Empire during World War I as long-range mine-layers.
Germany (Deutschland), officially the Federal Republic of Germany (Bundesrepublik Deutschland), is a sovereign state in central-western Europe.
A submarine (or simply sub) is a watercraft capable of independent operation underwater.
Type X (XB) U-boats were a special type of German submarine (U-boat).
World War I (often abbreviated as WWI or WW1), also known as the First World War, the Great War, or the War to End All Wars, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918.
World War II (often abbreviated to WWII or WW2), also known as the Second World War, was a global war that lasted from 1939 to 1945, although conflicts reflecting the ideological clash between what would become the Allied and Axis blocs began earlier.