Author Jeff McArthur's new book detailing a little-known story about the captivating life of Capone's long-lost big brother, Vincenzo "James" Capone, who dressed as a cowboy and became a famous federal Prohibition agent in Nebraska under the fake name, Richard "Two Gun" Hart. View Full Caption Jeff McArthur

CHICAGO — People who live in Chicago long enough typically think they know everything about our city’s most infamous criminal, Al Capone.

It’s as if details of the Prohibition-era gangster’s life seep into our Chicago consciousness through T-shirts, bumper stickers, biographies, movies and televised historical fictions, HBO’s "Boardwalk Empire" among them.

Now there’s a new book on the horizon detailing a little-known story about the captivating life of Capone’s long-lost big brother, Vincenzo “James” Capone.

Jeff McArthur discusses how he stumbled on Hart's story:

Some Capone aficionados probably know some of Vincenzo’s story — he ran away from home as a boy, fought in World War I, settled out West, changed his name to Richard Hart and worked as a federal Prohibition agent — ironically while his little brother became America’s most notorious bootlegger in Chicago.

In 1990, there was even a TV movie “The Lost Capone” that told an embellished tale of “Jimmy” Capone.

But author Jeff McArthur’s book, “Two Gun Hart: Lawman, Cowboy and Long-Lost Brother of Al Capone,” breaks down the details of the amazing life of the least-known Capone.

McArthur first heard the tale of “Two Gun” from his father, who grew up in Lincoln, Neb.

“My grandfather told my dad and my dad told me the story of the largest bank robbery in Nebraska and how Al Capone’s long-lost brother got the money back,” McArthur said of the robbery details included in the book. “I found a mention of [the robbery] in one of the other Capone books that said [Capone’s brother] lived in Homer, Neb., just a few miles away from my dad’s house.”

In Homer, McArthur sidled into a local bar, the kind of joint where everybody knows everybody, and announced he was looking for relatives of “Two Gun” Hart. And, of course, a tavern regular knew where McArthur could find Two Gun’s son Harry Hart, who lived just a few blocks from the author’s dad’s house in Lincoln.

“I looked up his number in the phone book. When I called, I got his answering machine that said, ‘You’ve reached Harry Hart, son of Richard 'Two Gun' Hart,’” McArthur said. “You could tell that he so badly wanted his father’s story told that he mentioned him on his answering machine.”

Interviews with the Hart family, family photos, newspaper stories, military and federal court records and a gold mine of letters between Hart and federal officials related to his work as a Prohibition agent out West detailed the eldest Capone’s reinvented life as a “half-Indian” lawman who, for a long while, dressed as a cowboy.

Describing Hart's dress style, McArthur wrote, “A pair of cowboy boots complete with spurs and embossed with a heart on each one appeared, followed by white pants, a white button-down shirt, and finally, a tall 10-gallon cowboy hat. Strapped to his waist were two ivory-handled six shooters. He looked like he had walked straight out of a silent western movie. … This was “Two Gun” Hart.”

Author Jeff McArthur's book “Two Gun Hart: Lawman, Cowboy and Long-Lost Brother of Al Capone," tells the little-known story of Al Capone's oldest brother. View Full Caption Jeff McArthur

McArthur details how Vincenzo Capone, after changing his identity to Richard Hart, met his wife while rescuing people from a flash flood, befriended Indian elders and became known as a “loose cannon” officer, one of the most successful Prohibition agents in the Midwest and — not unlike like his notorious brother Al — gained fame for his work.

Fans and detractors wrote Hart letters, some delivered to him in envelopes decorated with drawings of two guns and a heart on the envelopes and no address.

McArthur, who lives in Burbank, Calif., and works in the film industry, writes that Hart may have reunited with Al Capone as early as 1924 in Chicago, according to Chicago Evening American photographer Tony Berardi, who claims Capone introduced him to his lost sibling.

That same year, Capone met with Hart on a Nebraska Indian reservation, according to eyewitness reports cited in the book.

And by the 1940s, Hart had fully reunited with his family.

In the federal income tax trial of his brother Ralph “Bottles” Capone, Hart was outed as the “lost Capone brother” and forced to testify.

Hart, who wore his white 10-gallon cowboy hat on the stand, testified that he paid to start construction on a Mercer, Wis., cottage where Al Capone lived, which according to McArthur wasn’t outright perjury but definitely misrepresented the truth.

Despite being outed as Capone’s brother, the former lawman continued to live with his family in Nebraska as Richard J. Hart, the chosen name that adorns his tombstone in a cemetery overlooking Homer, Neb.

McArthur said he hoped Hart’s story would be made into a film one day, especially for Two Gun’s son, Harry Hart.

“Harry and the Hart family have watched other movies about their uncle and Eliot Ness,” McArthur said. “He believes that his father was a real hero in his own right and deserves to be recognized. And [Richard Hart’s] story, even if you take Al Capone out of it, is still amazing and heroic.

"The Capone connection only adds to the irony that an incredible law enforcement officer was the brother of one of the most infamous criminals in the world.”

“Two Gun Hart: Lawman, Cowboy and Long-Lost Brother of Al Capone” goes on sale March 16. For more information or to preorder visit bandwagononline.com.

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