Scant details are available about Gibson's early life, but it is believed that he was born somewhere in Louisiana's
Bienville Parish. He was first imprisoned in January 1904 at a
Baton Rouge prison for an unknown offence. According to him, he spiralled into a life of crime when he was "innocently railroaded to a southern penitentiary, where he had become a criminal [through] association." Justice William C. Barnette, a former district attorney for the Bienville Parish, indicated a different story: prior to 1907, Gibson, using the alias of "Monk", was put on trial for ambushing and shooting at another black man. As he was regarded as a good farmhand, Barnette defended Gibson, even employing legal talent to represent him in court. His client was still found guilty and sent off to the
Louisiana State Penitentiary. After serving his term, Gibson then left the state, travelling towards
Florida. Following this, Gibson engaged in criminal activities for little over a decade, allegedly committing thousands of burglaries and robberies, as well as several murders. Two often cited burglaries were committed in one night in June 1913, while he was in
Omaha, Nebraska. Gibson was arrested after the first successful burglary, but managed to escape, and with the manacles still on his wrists, he burglarized another home so he could get money to have the handcuffs filed off. He served time in four penitentiaries (in Louisiana,
Ohio, Florida and
Texas), escaping from the warden on two occasions (from Florida in 1917 and Texas in 1919). He never disclosed for what kind of offences he was imprisoned in Florida, but it later revealed by an oil company manager named Harris that Gibson had attempted to kill him during an argument. After their scuffle, the angered Mose returned with a gun and fired at Harris, grazing the top of his head and leaving a flesh wound. ==Murders==