The following lists events that happened during 1921 in South Africa.
- 3 – The second census of the Union of South Africa takes place.
- 24 – The Bulhoek Massacre takes place with an estimated 163 killed.
- 30 – The Communist Party of South Africa is established.
- Unknown date
- Dagbreek men's residence opens at Stellenbosch University.
- 10 September – John Tengo Jabavu, editor of South Africa's first newspaper in Xhosa. (b. 1859)
Railway lines openedEdit
- 1 November – Transvaal – Pretoria West to Roberts Heights, 7 miles 38 chains (12.0 kilometres).
- 28 November – Natal – Booth Junction to Cato Ridge, 39 miles 58 chains (63.9 kilometres).
Two new Cape gauge locomotive types enter service on the South African Railways (SAR):
- Archontology.org: A Guide for Study of Historical Offices: South Africa: Governors-General: 1910-1961 (Accessed on 14 April 2017)
- Statement Showing, in Chronological Order, the Date of Opening and the Mileage of Each Section of Railway, Statement No. 19, p. 188, ref. no. 200954-13
- Holland, D. F. (1972). Steam Locomotives of the South African Railways. Vol. 2: 1910-1955 (1st ed.). Newton Abbott, England: David & Charles. pp. 41–42. ISBN 978-0-7153-5427-8.
- Hamilton, Gavin N., The Garratt Locomotive - Garratt Locomotives produced by Beyer, Peacock, retrieved 10 November 2012
- Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 88–89. ISBN 0869772112.