This article analyses the place of Christian proslavery in the era of amelioration through the lens of the career of the Rev. James Curtin (1765-1845). Curtin is best known for his role in the baptism of Mary Prince, and the History of Mary Prince that made her famous. Curtin was a crucial proslavery advocate in the subsequent libel cases involving Thomas Pringle, the Secretary of the Anti-Slavery Society, the Wood family who enslaved Mary Prince and the British proslavery faction led by the pugnacious James MacQueen of the Glasgow Courier . It is argued that a "history of James Curtin" provides valuable insight into the character of British proslavery, and the stages by which Curtin was transformed from Roman Catholic priest to proslavery pariah in the course of a long and contentious life.