Archbishop Sancroft. William Sancroft (30 January 1617 - 24 November 1693) was the 79th Archbishop of Canterbury, and was one of the Seven Bishops imprisoned in 1688 for seditious libel against King James II, over his opposition to the king's Declaration of Indulgence. Deprived of his office in 1690 for refusing to swear allegiance to William and Mary, he later enabled and supported the consecration of new nonjuring bishops leading to the nonjuring schism.