While there have been many mobsters in Chicago over the years, Giacomo Colosimo was one of the most important in his time. He certainly made his mark on organized crime in Chicago and his name has gone down in mobster history. Here are 15 facts about this notorious Italian-American gangster.
- His name at birth was Vincenzo Colosimo.
- Giacomo Colosimo is also known as James Colosimo, Big Jim Colosimo, and Diamond Jim.
- He earned the nickname Diamond Jim because of his preference for white suits and love of pins, rings, and jewelry.
- Colosimo was born in Calabria, Italy, on February 16, 1878.
- He was just 17 when he immigrated to the United States and became a petty criminal in Chicago.
- He was a precinct captain for John Coughlin and Michael ‘Hinky Dink’ Kenna. He later became their bagman.
- He married Victoria Moresco in 1902. Moresco was a well-established Madame at a brothel.
- In addition to running brothels, Colosimo was involved in racketeering and illegal gambling.
- He married Dale Winter, his second wife, in 1920. He had been married for just over a week when he was murdered.
- Colosimo once oversaw over 200 brothels. These included the Cermac in the Near South Side and the Four Deuces at Wabash.
- He is best-known as the boss of the Chicago Outfit, although the gang was not known by this name at the time. Colosimo was the first gang leader in Chicago to organize the disparate parts of the crime scene in this city.
- He once had a restaurant called Colosimo’s Café. This is now a 1920s gangster-themed dinner theater called Tommy Guns Garage.
- Giacomo Colosimo died from multiple shot wounds in Chicago, Illinois, on May 11, 1920.
- He is buried at Oak Woods Cemetery in Chicago.
- When Colosimo dies, John Torrio took over his gang before being replaced by the infamous Al Capone.

Sources
- Main Image: Wiki