He was the third of six children, born to Hermanus Bernardus Swart (1866–1949) and Aletta Catharina Robberts (1870–1929). The Anglo Boer War (Second Boer War) broke out when he was five years old. During the war, his mother and the children were interned at the Winburg concentration camp. Out of the three boys, one died while in the concentration camp. His father was wounded and captured by the British during the Battle of Paardeberg. He became a prisoner-of-war and stayed in Groenpunt and Simonstad until the end of the war.