Schwarz was born on 3 March 1932 in Sevlus (modern day Vynohradiv) in the Carpathian Mountains, which was then the most easterly part of Czechoslovakia. In 1941 32% of the town’s population was Jewish.
Little is known about Schwarz’s family or childhood.
In 1938, Sevlus and the surrounding area were annexed by Hungary with these territories formally incorporated into Hungary in 1939. The Nazi’s occupied Hungary in March 1944 and installed a puppet government. That government participated in the Holocaust.