10 – The League of Nations is established as the Treaty of Versailles goes into effect.
1 – The South African Air Force (SAAF) is established, the second autonomous Air Force in the world after the Royal Air Force (RAF).
20 – Prince Arthur of Connaught is appointed the 3rd Governor-General of the Union of South Africa.
17 – South Africa is granted a League of Nations Class C mandate over South West Africa.
12 May – Basil Gerald Stapleton DFC, World War II fighter pilot, in Durban. (d. 2010)
8 August – Nimrod Sejake, activist, in Evaton. (d. 2004)
11 December – Olive Shreiner, author and feminist, in Cape Town. (b. 1855)
The South African Railways places thirty Class 12B 4-8-2 Mountain type steam locomotives in mainline service.
1920 in South Africa Wikipedia