Owen 'Owney' Madden, the notorious gangster of New York's Prohibition era, was known as the Duke of the West Side. He became the inspiration for Hollywood gangster films, all while sporting a signature cloth cap instead of the typical trilby and Tommy gun.

Born on December 18, 1891, in Leeds, England, to Irish immigrant parents, Madden's life took a turn when his family moved to Wigan. At a young age, he performed in music halls, cultivating a love for show business.

In 1902, the family immigrated to the United States, settling in the rough neighborhood of Hell's Kitchen, New York. Despite an initial desire to stay away from crime, Madden joined the Irish-American gang The Gophers at the age of 12, quickly rising through their ranks.

By 14, he committed his first major crime, robbing $500 from a victim he had severely beaten. His violent reputation grew, and by 18, he was rumored to have killed five men, earning the nickname 'The Killer'.

In 1911, at age 20, he was sentenced to 20 years in Sing Sing for the manslaughter of 'Little Patsy Doyle'. After serving seven years, he capitalized on the Prohibition era by joining the Dutch Schultz organization.

As he delved deeper into crime, he began running his own racket by hijacking delivery trucks and hired up-and-coming actor George Raft as his driver.

Notably, Madden began a tumultuous relationship with actress Mae West, backing her controversial Broadway show, 'Sex', which led to arrests for public indecency. He also acquired The Cotton Club, a famed nightclub notable for its racially exclusive policy despite being in a predominately Black area.

Despite his celebrity lifestyle, Madden faced increasing scrutiny from law enforcement and the IRS. To escape mounting pressures, he struck a $1 million deal with prosecutors and relocated to Hot Springs, Arkansas, where he married Agnes Demby.

Following the repeal of Prohibition on December 5, 1933, which severely impacted his income, Madden shifted his focus to illegal gambling. He established a hotel and casino, becoming a refuge for prominent gangsters like Meyer Lansky and Lucky Luciano.

Madden lived out his life in Arkansas with Agnes, passing away peacefully on April 24, 1965, at the age of 73. Graham Nown, his biographer, described him as an "unlikeliest gangster," maintaining his British passport and a strong accent while fostering a hobby of breeding pigeons.