Northern Rhodesia the British South Africa Company administered territory of North-Western Rhodesia (now in Zambia), and Portuguese Angola although its boundary with Angola was not marked-out on the ground until later. The northern border of the British territory in North-Eastern Rhodesia and the British Central Africa Protectorate was agreed as part of an Anglo-German Convention in 1890, which also fixed the very short boundary between North-Western Rhodesia and German South-West Africa, now Namibia. The boundary between the Congo Free State and British territory was fixed by a treaty in 1894, although there were some minor adjustments up to the 1930s. Boundaries with
Northern Rhodesia to justify the capital cost of building a railway to the coast, but expeditions between 1899 and 1901 proved their value. Copper deposits found in Northern Rhodesia before the First World War proved uneconomic to develop. In 1906 Union Minière du Haut Katanga was formed to exploit the Katanga mines. King Leopold wanted a railway entirely in Congolese territory, linked to the Congo River, but in 1908, he agreed with the British South Africa Company to continue the Rhodesian railway to Elizabethville and the mines. Between 1912, when full-scale copper production began, until 1928 when a Congolese line was completed,