Jack Saul (1857-1904) was an Irish prostitute and author of popular erotica. Born in a Dublin tenement slum, Saul was raised in a poor Catholic family alongside seven siblings. He turned to sex work at a young age, moving to London in 1879 to earn more money for his impoverished mother. There, he gained a reputation as a professional prostitute and was swept up in the Cleveland Street scandal of 1887. During the trial, Saul's confession, which likely risked implicating aristocrats and members of the Royal Family, resulted in his release from custody. In 1881, the erotic novel The Sins of the Cities of the Plain, appeared in print. Marketed as Saul's memoirs, the novel was likely written through the combined efforts of Saul and either Simeon Solomon or James Campbell Reddie, both of whom wrote popular Victorian erotica.