In the late summer of 1933, with the Great Depression holding Chicago in a frozen grip, twenty-two-year-old Jacob Rubenstein and his sister Eva packed a single suitcase and looked west. Under the sun-drenched palm trees of California, a strange transformation occurred. The volatile, quick-tempered kid from the West Side tenements seemed to vanish, replaced by a well-mannered, meticulously dressed young gentleman who openly admired local beat cops and managed newspaper subscription crews. Yet, the street-hustler DNA remained active underneath his polished veneer as he ran lucrative racetrack tip sheets from Santa Anita to Bay Meadows.
But this fragile West Coast peace was shattered in 1937 when his mother, Fanny, suffered a complete psychiatric collapse. Returning to the familiar grime and chaos of his family's Chicago home, the polished gentleman dissolved. Jacob immediately plunged back into the raw, competitive arena of the streets—scalping tickets, selling cheap watches out of his pockets, and violently beating a man to the pavement who hurled an anti-Semitic slur at him.
Desperate for a real position of authority and respect, Jacob found his calling in late 1937 as an organizer for the Scrap Iron and Junk Handlers Union. It was here that he met the ultimate mentor who would redefine his life: Leon Cook, the union’s brilliant, idealistic, college-educated attorney. Jacob idolized Cook, pouring his manic energy into the union while frequently serving as its blunt instrument and "muscle" to keep hostile employers and wildcat strikes in line.
Then came the cold night of December 8, 1939, when a bitter power struggle ended in gunfire. Mob-aligned union president John Martin shot Leon Cook at point-blank range, a lethal blow that eventually claimed Cook's life and allowed the Chicago syndicate to seize control. Shattered and violently frozen out by the mob, twenty-eight-year-old Jacob made a profound, deeply emotional choice to preserve his mentor's memory: he legally adopted Cook’s first name as his own middle name. From that moment on, he was Jacob Leon Rubenstein—and later, Jack Leon Ruby. Every time he signed a document, introduced himself to a Dallas police officer, or handed out a strip club business card, he carried the name of a murdered man and the heavy shadow of his violent past.
