Weissmann was a long time member of the Jewish community Osijek. On 20 April 1926 Weissmann and several others Jewish athletes founded the "Rowing sport club Bar Kohba", which he also presided. During World War II, as a Jew, he was persecuted and forced to leave Osijek. He escaped to Jastrebarsko where he worked as physician from 1942 to 1945. After the war Weissmann returned to Osijek where he died from a heart attack.[3] He was buried at the Jewish cemetery Osijek.[4]