Dov-Ber (or Beryl) Rosofsky was born in New York City to Isidore "Itchik" Rosofsky and Sarah Epstein Rosofsky. His father was a Talmudic scholar who had emigrated to America from his native Brest-Litovsk after barely surviving a pogrom. The family then moved from New York to Chicago. Isidore became a rabbi and owner of a small vegetable shop in Chicago's Maxwell Street neighborhood, a vibrant Jewish ghetto akin to the New York's Lower East Side of the 1920s and '30s. Dov-Ber was being raised to follow in his footsteps.