Apologia Pro Vita Sua is John Henry Newman's defense of his religious opinions, published in 1864 in response to Charles Kingsley of the Church of England. Friction during the years from 1833 to 1841 had led Newman and his allies in the Oxford movement to publish a statement to which Newman was a contributor. The tensions culminated in Newman's 1845 resignation as Anglican vicar of St. Mary's, Oxford and his departure from the Anglican Church and conversion to Roman Catholicism. Apologia Pro Vita Sua was written in response to attacks from Kingsley of the broad church party, and Newman's rival in the controversy surrounding the Tractarian movement, who responded to Newman's conversion with attacks impeaching his truthfulness and honor. The book was a spiritual autobiographical defense to Kingsley's attacks.