Heligoland was a small island in the North Sea, roughly three hours off the northern coast of Germany. Formerly under the control of the British Empire, Heligoland was traded to the Germans for the African island of Zanzibar in the Heligoland-Zanzibar Treaty of 1890. The trade was made because Germany felt threatened by a foreign power owning such a militarily strategic island just off of its own shores.
