Kasanga, known as Bismarckburg during the German colonial rule, is a town in Rukwa Region, Tanzania. It is located at around 8°27′30″S 31°8′10″E, on the shore of Lake Tanganyika, 810 m above sea level.

German East Africa was a German colony in the African Great Lakes region, which included present-day Burundi, Rwanda, the Tanzania mainland, and the Kionga Triangle, a small region later incorporated into Mozambique. GEA's area was 994,996 km2 (384,170 sq mi), which was nearly three times the area of present-day Germany and almost double the area of metropolitan Germany at the time.