

The Irish Mob is one of the oldest organized crime groups in the United States, in existence since the early 19th century. Originating in Irish American street gangs of the 19th century
Irish gangs date at least to the mid-19th century when street gangs waged battles for control of New York City neighborhoods with colorful names like Dead Rabbits and 40 Thieves. A new kind of Irish gangster emerged during Prohibition in the 1920s when rival organizations fought for bootlegging and gambling operations.
Irish gangs conducted criminal operations unrivaled for most of the 19th century until the 1880s when Italian immigrants began to arrive and established the Black Hand and later the Cosa Nostra.
Jewish and Italian mobsters encroached on Irish bootlegging, dog racing and gambling operations in Chicago, leading to a bloody war that fostered the modern gangster.
Italian mobster Al Capone planned the St. Valentine's Day Massacre on Feb. 14, 1929, in which six members of Bugs Moran's Irish gang and a bystander were killed in a dispute.