Constantinople Flotilla

The Constantinople flotilla was an Imperial German Navy formation set up to prosecute the U-boat campaign against Allied shipping in the Mediterranean and the Black Sea in support of Germany’s ally, the Ottoman Empire. Despite its official name, the Mediterranean Division (U-boote der Mittelmeer in Konstantinopel), it saw little service there, operating mostly against Russian shipping in the Black Sea.

The Constantinople Flotilla had a maximum strength of 11 U–boats but due to the unfavourable conditions for commerce raiding in the Black Sea saw little success during its three years of operations. In three years of operation, the force sank ships totalling 117,093 GRT. 14 U-boats served in the Constantinople Flotilla; 6 were lost operationally.

In 1917 the force was amalgamated with the Pola Flotilla, coming under the command of the U-Boat Leader, Mediterranean (Führer der U-boote im Mittelmeer) there; the unit was renamed the  Constantinople Half-Flotilla (U-Halbflotille Konstantinopel).

In 1918, with the collapse of the Central Powers, the U-boats were scuttled, or fled to join the Pola boats in their evacuation to Germany.