Who is Jack Ruby from Case Closed: Lee Harvey Oswald and the Assassination of JFK and what is their importance?

Jack Ruby was born on March 25, 1911 in Chicago. He was the fifth of eight children in an Orthodox Jewish family. His parents separated when he was ten years old. He began working as a hustler at an early age. His mother placed him in psychiatric care at the age of eleven because she could not control him. He was placed in foster care the following year for eighteen months. Ruby moved to California in 1933 but returned to Chicago in 1937 and began to work as a union organizer. He, his brother and two friends began the Spartan Novelty Company in 1941.