Tunstall, Or Tonstall, Cuthbert, an English prelate, born at Hatchford, Yorkshire, in 1474 or 1475, died at Lambeth palace, Nov. 18, 1559. He was educated at Oxford and Cambridge, became a fellow of the latter university, and then studied at Padua. He became rector of Harrow-on-the-Hill in 1511, and in 1515 archdeacon of Chester. In 1516 he was appointed master of the rolls, and sent as commissioner to Brussels, where he concluded two treaties with Charles I. of Spain (afterward Charles V.), and became acquainted with Erasmus. In 1521 he was made dean of Salisbury, in 1522 bishop of London, and in 1523 lord privy seal; and he was twice ambassador to Spain and France. In 1530 he was translated to the bishopric of Durham. He soon after resigned the privy seal, but he remained bishop through all the changes made by Henry VIII. and Edward VI., and also had a place in the councils of state, till October, 1552, when he was deprived of his bishopric and committed to the tower. Mary reinstated him, but declining the oath of supremacy on Elizabeth's accession, he was again deprived in July, 1559, and remained the guest of Parker, archbishop of Canterbury, till his death.

His works include In Laudem Matrimonii (4to, London, 1518); De Arte Supputandi Libri IV. (4to, 1522), a treatise on arithmetic, often reprinted; "Compendium and Synopsis," an abridgment of Aristotle's " Ethics" (8vo, Paris, 1554); "A Defence of Predestination" (4to, Antwerp, 1555); and a volume of prayers (8vo, 1558).