When John Holloway Slaughter was born on 3 September 1858, in Alabama, United States, his father, Oliver P Slaughter, was 30 and his mother, Eliza Davis, was 25. He married Milbry Knighton on 3 November 1881, in Webster, Louisiana, United States. They were the parents of at least 3 sons and 1 daughter. He lived in Ward Two, Grant, Louisiana, United States in 1900 and Police Jury Ward 5, La Salle, Louisiana, United States in 1920. He died on 7 May 1922, in Rogers, La Salle, Louisiana, United States, at the age of 63, and was buried in La Salle, Louisiana, United States.