European exploration of Africa 1840s, so that around the midpoint of the 19th century and the beginning of the colonial Scramble for Africa, the unexplored parts were now limited to what would turn out to be the Congo Basin and the African Great Lakes. This "Heart of Africa" remained one of the last remaining "blank spots" on world maps of the later 19th century (alongside the Arctic, Antarctic and the interior of the Amazon basin). It was left for 19th-century European explorers, including those searching for the famed sources of the Nile, notably John Hanning Speke, Sir Richard Burton, David Livingstone and Henry Morton
British diaspora in Africa proclaimed a British colony in 1843. Following the defeat of the Boers in the Second Boer War in 1902, Britain annexed the Boer Republics of the Transvaal Republic and the Orange Free State. Scottish medical missionary David Livingstone famously explored Africa, and it is believed he was the first European to set eyes on Victoria Falls in 1855. He is a key character in African history, being one of the first well-known Britons to believe his heart was in Africa. In the late nineteenth century, the discovery of gold in the Witwatersrand and diamonds in Kimberley encouraged further settlement by