Complex sentence: His great-grandfather Samuel "Bo" Bregman who immigrated from Russia to Washington, D.C., around 1900, and married Sadie Hurwitz Bregman, promoted boxing cards that featured among others Joe Louis, Billy Conn, and Bob Foster.
Split into simpler sentences: His great-grandfather Samuel "Bo" Bregman immigrated from Russia to Washington, D.C., around 1900, and married Sadie Hurwitz Bregman. He promoted boxing cards that featured, among others, Joe Louis, Billy Conn, and Bob Foster.