Dezider was the oldest of three children born to Hungarian-speaking Jewish parents in the city of Kosice in the southeastern part of Czechoslovakia known as Slovakia. As a young boy, he attended a Jewish elementary school. His father was a tailor whose workshop was in the Gruenberger's small apartment.
1933-39: After I finished elementary school, I entered secondary school with a view to going on to the university. The language of instruction was Slovak, and Jews faced no discrimination until November 1938 when Hungarian troops marched into southern Slovakia. With Germany's blessing, Kosice became part of Hungary and was renamed Kassa. Our new Hungarian rulers introduced anti-Jewish laws.
1940-44: I managed to finish my secondary education in 1940, but because I was Jewish I wasn't allowed to go on to the university. In 1941 the Hungarians interned my family because we were considered "aliens." Two years later, I became a forced laborer for the Hungarian army. I was put to work in the Carpathian mountains building defenses, mining roads, and carrying ammunition. A year later, when we heard that the advancing Soviet army was nearby, my friend and I took heart and escaped. We were hidden by a peasant.
Dezider was liberated near Munkacevo by Soviet troops on October 28, 1944. After the war, he returned to Czechoslovakia. He emigrated to the United States in 1968.