By the end of 1894, the territories over which the BSAC had concessions or treaties, collectively called "Zambesia" after the Zambezi River flowing through the middle, comprised an area of 1,143,000 km2 between the Limpopo River and Lake Tanganyika. In May 1895, its name was officially changed to "Rhodesia", reflecting Rhodes's popularity among settlers who had been using the name informally since 1891. The designation Southern Rhodesia was officially adopted in 1898 for the part south of the Zambezi, which later became Zimbabwe; and the designations North-Western and North-Eastern Rhodesia were used from 1895 for the territory which later became Northern Rhodesia, then Zambia. He built a house for himself in 1897 in Bulawayo.