Heligoland-Zanzibar Treaty

The Heligoland–Zanzibar Treaty (German: Helgoland-Sansibar-Vertrag; also known as the Anglo-German Agreement of 1890) was an agreement signed on 1 July 1890 between the German Empire and the United Kingdom. Germany gained the small but strategic Heligoland archipelago, which its new navy needed to control the new Kiel Canal and the approaches to Germany's North Sea ports. In exchange, Germany gave up its rights in the Zanzibar region in Africa, allowing Zanzibar to provide a key link in the British control of East Africa.

Germany gained the islands of Heligoland (German: Helgoland) in the North Sea, originally part of Danish Holstein-Gottorp but since 1814 a British possession, the so-called Caprivi Strip in what is now Namibia, and a free hand to control and acquire the coast of Dar es Salaam that would form the core of German East Africa (later Tanganyika, now the mainland component of Tanzania).

In exchange, Germany handed over to Britain the protectorate over the small sultanate of Wituland (Deutsch-Witu, on the Kenyan coast) and parts of East Africa vital for the British to build a railway to Lake Victoria, and pledged not to interfere with British actions vis-à-vis the independent Sultanate of Zanzibar (i.e. the islands of Unguja and Pemba). In addition, the treaty established the German sphere of interest in German South West Africa (most of present-day Namibia) and settled the borders between German Togoland and the British Gold Coast (now Ghana), as well as between German Kamerun and British Nigeria.

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