Marian Hemar was born to a Jewish family on 6 April 1901 in Lwów. He studied medicine and philosophy at the Jan Kazimierz University locally, and took part in the Defense of Lwów in 1918 and 1919 as a volunteer on the Polish side of the Polish–Ukrainian War of independence. At the invitation of Jerzy Boczkowski, director of the legendary ' Theatre, he left for Warsaw in 1924. By 1925 he was already a well-known personality in the arts community of Warsaw, working at the "Qui Pro Quo" cabaret with Julian Tuwim. He was a key figure in the productions of "Banda", ', and "" ("Barber of Warsaw") cabarets; as well as the author of hundreds of Polish Radio sketches. He also wrote "shmontses (szmonces)" – Jewish jokes, monologues and sketches – and jointly composed political sketches with poets Julian Tuwim and Antoni Słonimski.