Dejan was one of nine children born to well-to-do Serbian Orthodox parents in a town in the Croatian part of Yugoslavia. In 1916 he was drafted into the Austro-Hungarian army, but he deserted and joined the Serbian army. Dejan graduated from medical school in 1923 and opened a practice in Belgrade. In 1926 he married a wealthy Serb woman from Jasenovac. The couple had no children.
1933-39: Dejan had a successful obstetrics-gynecology practice in Belgrade. He and his wife were prosperous and had an active social life. Dejan traveled frequently, often to Paris and Switzerland. He loved trout fishing and his favorite streams were in the rugged highlands of Bosnia. When war broke out in Europe in September 1939, Yugoslavia declared itself neutral.
1940-42: Ten days after Yugoslavia's pro-German leaders were overthrown by Serbian army officers, German planes bombed Belgrade. On April 6, 1941, Germany invaded Yugoslavia. Dejan fled to the remote Bosnian region of Govza, familiar to him from his fishing trips. He sought safety with the Muslim inhabitants, but was turned over to a unit of the thirteenth Waffen SS "Handschar" Division composed predominantly of Muslim Yugoslavs. Dejan's legs and hands were broken, his eyes gouged, and he was skinned alive.
On August 2, 1943, Dejan, barely alive, was hanged in Govza by Muslim soldiers from the SS "Handschar" division. Dejan was 46 years old.