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—depicted in Herbert Asbury's 1928 book The Gangs of New York—the Irish Mob has appeared in most major American cities, including Boston, New York City, Philadelphia, Chicago and New Orleans.

Outside of Ireland itself, Canada, Australia and the United Kingdom also have histories of Irish gang activities.

Boston has a well-chronicled history of Irish mob activity, particularly in the heavily Irish-American neighborhoods like Somerville, Charlestown, South Boston ("Southie"), Dorchester and Roxbury where the earliest Irish gangsters arose during Prohibition. Frank Wallace of the Gustin Gang dominated Boston's underworld until his death in 1931, when he was ambushed by Italian gangsters in the North End. Numerous gang wars between rival Irish gangs during the early and mid 20th century would contribute to their decline.

Irish may refer to:

Mob may refer to:

Frank Morrison Spillane (March 9, 1918 – July 17, 2006), better known as Mickey Spillane, was an American author of crime novels, many featuring his signature detective character, Mike Hammer. More than 225 million copies of his books have sold internationally. In 1980, Spillane was responsible for seven of the top 15 all-time best-selling fiction titles in the U.S.

Born in Brooklyn, New York City, and raised in Elizabeth, New Jersey, Spillane was the only child of his Irish bartender father, John Joseph Spillane, and his Scottish mother, Catherine Anne. Spillane attended Erasmus Hall High School, graduating in 1935. He started writing while in high school, briefly attended Fort Hays State College in Kansas and worked a variety of jobs, including summers as a life-guard at Breezy Point, Queens, and a period as a trampoline artist for the Ringling Bros. and Barnum & Bailey Circus.

During World War II Spillane enlisted in the Army Air Corps, becoming a fighter pilot and a flight instructor. While flying over Murrells Inlet, South Carolina, he said, "That is where I want to live." Later, he would use his celebrity status to publicize the Grand Strand on TV, but when it became a popular resort area and traffic became a problem, Spillane said, "I shouldn't have told people about it."

James Joseph "Whitey" Bulger, Jr. (born September 3, 1929) is a former organized crime figure from Boston, Massachusetts. Local folklore depicted Bulger as a Robin Hood–style social bandit dedicated to protecting the neighborhood and its residents. Bulger allegedly masterminded a protection racket targeting drug kingpins and those running illegal gambling operations. Based upon the testimony of former associates, Federal prosecutors have indicted Bulger for 19 murders.

Beginning in 1975, Bulger served as an informant for the Federal Bureau of Investigation (FBI). As a result, the Bureau largely ignored his organization in exchange for information about the inner workings of the Italian American Patriarca crime family. Beginning in 1997, the New England media exposed criminal actions by federal, state, and local law enforcement officials tied to Bulger. For the FBI especially, this has caused great embarrassment. On December 23, 1994, after being tipped off by his former FBI handler about a pending indictment under the RICO Act, Bulger fled Boston and went into hiding. For sixteen years, he remained at large. For twelve of those years, Bulger was prominently listed on the FBI Ten Most Wanted Fugitives list.