Frank was born in Texas in 1884 but was soon moved to Brooklyn, New York with his parents. In 1906, Frank graduated with a degree in mechanical engineering from Cornell University. He later spent nine months apprenticing in Europe, after which he moved to Atlanta, Georgia where he would become supervisor of the National Pencil Factory. In April 1913, after Frank had a been supervisor of the factory for about five years, thirteen-year-old Mary Phagan was fired from her job due to a late shipment of an essential part. On April 26th, Phagan was brutally murdered after picking up her $1.20 check from the factory.
Over the course of a few days, multiple men were arrested under suspicion of having committed this horrific crime, including Newt Lee, a black watchman who found Phagan's bloodied body at the scene. Lee was repeatedly questioned and almost the victim of a lynch mob himself before police prevented the mob from killing him. Over the following month, the questioning continued. A fingerprint expert presented evidence that cleared Lee. With the public demanding the capture of the perpetrator, and with many locals assuming the guilt of Leo Frank, the Jewish supervisor was indicted by a grand jury for the murder of Mary Phagan.
Two months later, on July 28, 1913, Frank's trial began. The trial lasted for 25 days, and ultimately, Leo Frank was sentenced to death by hanging. Frank's attorney's requested an appeal, but the Fulton County Superior Court and the US Supreme Court denied these requests. Frank's attorney appealed to the governor who personally led an exhaustive investigation that included 10,000 documents and led him to believe in Frank's innocence. The governor did not commute Frank, but instead commuted his sentence to life in prison and anticipated his innocence would be established through another appeal.
On June 21, 1915, Frank was taken to Georgia State Penitentiary after serving time in the Fulton County Prison. One month later, and nearly two full years after Phagan was found murdered, approximately 30 men kidnapped Frank from the state prison and drove him back to Marietta, near Phagan's childhood home, where he was hanged and then beaten by angry members of the crowd. No one was identified for participating in this lynching and the governor fled Georgia with his family a few days after the lynching.