|Died||3 March 1942 (aged 26)|
Štajnberger was born on 15 February 1916 in Zagreb to a Jewish family of Mavro Štajnberger. In his early youth he joined the Young Communist League of Yugoslavia. In 1937, during the Spanish Civil War he went to Spain as a volunteer, soon to be included in the ranks of the International Brigades. He was known as a brave and resourceful fighter. In 1938, Štajnberger became a member of the Communist Party of Yugoslavia. Afterwards he returned to Zagreb.
During World War II, he was imprisoned at the concentration camps in France from which he was deported for forced labour to Nazi Germany. He managed to escape in mid-July 1941, and move to the occupied territory of Yugoslavia, in Croatia. Upon arrival, Štajnberger briefly stayed in Zagreb, and then moved to the liberated territory in Kordun. He helped organize the first Partisan units in Perjasica, Kestenjac, Veljun, Kloloć and Kladuša. Among the Partisans and the people of Kordun at the time, he was known by his birth name Adolf.
At the beginning of 1942, Italian fascists with the help from the Chetniks captured Štajnberger with fellow fighters Robert Domany, Branko Latas and Stevo Čuturilo. All of them were killed by Chetniks, and afterwards their bodies were thrown in the pit of Balinka.
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