 The South Africa Act was the third major piece of legislation passed by the Parliament of the United Kingdom with the intent of uniting various British colonies and granting them some degree of autonomy.Earlier, the British North America Act, 1867 had united three colonies (Canada – which became Ontario and Quebec – Nova Scotia, and New Brunswick) and the Commonwealth of Australia Constitution Act, 1900 had united the Australian colonies.In the aftermath of the Anglo-Boer War (1899–1902), Britain re-annexed the South African Republic and the Orange Free State, two hitherto independent Boer republics.