Zambezi Region with the United Kingdom. Leo von Caprivi arranged for the Caprivi strip to be annexed to German South West Africa in order to give Germany access to the Zambezi River as part of the Heligoland-Zanzibar Treaty. The German motivation behind the swap was to acquire a strip of land linking German South West Africa with the Zambezi River, providing easy access to Tanganyika (Tanzania) and an outlet to the Indian Ocean. Unfortunately for the Germans, the British colonisation of Rhodesia (Zimbabwe and Zambia) stopped them well upstream of Victoria Falls, which proved a considerable barrier to navigation on the Zambezi.
Zambezi sourced from the same great internal lake. The Portuguese were also told that the Mozambican Espirito Santo "river" (actually an estuary formed by the Umbeluzi, Matola and Tembe rivers) was sourced from a lake (hence its outlet became known as Delagoa Bay). As a result, several old maps depict the Zambezi and the "Espirito Santo" rivers converging deep in the interior, at the same lake. However, the Bisa-derived etymology is not without dispute. In 1845, W.D. Cooley, examining Pereira's notes, concluded the term "Zambezi" derives not from the Bisa people, but rather from the Bantu term "mbege"/"mbeze" ("fish"), and consequently