Military history of South Africa during World War II Westminster with its head of state being the British king, the South African Prime Minister on 1 September 1939 was J.B.M. Hertzog – the leader of the pro-Afrikaner and anti-British National Party. The National Party had joined in a unity government with the pro-British South African Party of Jan Smuts in 1934 as the United Party. Hertzog's problem was that South Africa was constitutionally obligated to support Great Britain against Nazi Germany. The Polish-British Common Defence Pact obligated Britain, and in turn its dominions, to help Poland if attacked by the Nazis. When Adolf Hitler's forces attacked Poland on 1
Prime Minister of Australia prime minister, otherwise William McMahon63. Robert Menzies was the oldest person to ever be prime minister, leaving office at 71 years old. The longest-serving Prime Minister was Sir Robert Menzies, who served in office twice: from 26 April 1939 to 28 August 1941, and again from 19 December 1949 to 26 January 1966. In total Robert Menzies spent 18 years, 5 months and 12 days in office. He served under the United Australia Party and the Liberal Party respectively. The shortest-serving Prime Minister was Frank Forde, who was appointed to the position on 6 July 1945 after the death of