Example image of eyePlorer eyePlorer map for 'Union of South Africa': South Africa Cape Colony Colony of Natal Orange Free State Transvaal German South-West Africa League of Nations Commonwealth of Nations Commonwealth realm Dominion Republic Australia Federation Unitary state Bicameralism House of Assembly Parliament Senate British Empire Monarchy of the United Kingdom Statute of Westminster 1931 Monarchy of South Africa Governor-General of the Union of South Africa Head of government Prime Minister of South Africa Afrikaner Boer Louis Botha Afrikaans Dutch language Entrenched clause Official language South Africa under apartheid South African republic referendum, 1960 South Africa Act 1909 Second Boer War George Grey Henry Herbert, 4th Earl of Carnarvon Secretary of State for the Colonies Southern Rhodesia Southern Rhodesian government referendum, 1922 British South Africa Company Jan Smuts South West Africa Trusteeship Namibia Walvis Bay Balfour Declaration of 1926 Colonial Laws Validity Act 1865 1st Infantry Brigade (South Africa)