Before 1902, the southern part of Africa that is now South Africa was under the hegemony of Great Britain. There also were two self-proclaimed independent states: Transvaal, and the Orange Free State. The British and the Boers fought two wars, known as the First Boer War (1880–1881) and the Second Boer War (1899–1902); after the second war, in which the British prevailed, both republics were incorporated into the British Empire. On May 31, 1910, the two ex-republics and the British colonies of the Cape and Natal formed the Union of South Africa, a self-governing dominion of the British Empire.