The 1890 British Ultimatum is an ultimatum by the British government delivered on January 11, 1890 to Portugal.
The ultimatum forces the retreat of Portuguese military forces from areas that had been claimed by Portugal on the basis of historical discovery and recent exploration, but which the United Kingdom claims on the basis of effective occupation.
Portugal had attempted to claim a large area of land between its colonies of Mozambique and Angola including most of present-day Zimbabwe and Zambia and a large part of Malawi, which had been included in Portugal's "Rose-colored Map".
It will sometimes be claimed that the British government's objections had arisen because the Portuguese claims clashed with its aspirations to create a Cape to Cairo Railway, linking its colonies from the south of Africa to those in the north.
This seems unlikely, as in 1890 Germany already controls German East Africa, now Tanzania, and Sudan is independent under Muhammad Ahmad.
Rather, the British government is pressed into taking action by Cecil Rhodes, whose British South Africa Company had been founded in 1888 south of the Zambezi and the African Lakes Company and British missionaries to the north.
