The Battle for Lake Tanganyika was a series of naval engagements that took place between elements of the Royal Navy, Force Publique and the Kaiserliche Marine between December 1915 and February 1916, during the First World War. The intention was to secure control of the strategically important Lake Tanganyika, which had been dominated by German naval units since the beginning of the war. The British forces, consisting of two motor boats named HMS Mimi and HMS Toutou under the command of the eccentric Lieutenant-Commander Geoffrey Spicer-Simson were transported to South Africa and from there by railway, river and by being dragged through the African jungle, to the lake.
In two short engagements the small motor boats attacked and defeated two of their German opponents. In the first action, on 26 December 1915 the Kingani was damaged and captured, becoming HMS Fifi. In the second, the small flotilla overwhelmed and sank the Hedwig von Wissman. The Germans maintained a third large and heavily armed craft on the lake, the Graf von Götzen, this craft was attacked indecisively by Belgian aircraft and was later scuttled. Developments in the land-based conflict caused the Germans to withdraw from the lake.