Sir John Trevor (1596–1673), of Trevalyn Hall in Denbighshire, was a Welsh Puritan Member of Parliament during the reigns of James I and Charles I, and a member of the Council of State during the Commonwealth. He inherited Trevalyn on the death of his uncle Richard Trevor in 1638.
Trevor, whose father Sir John Trevor was Surveyor of the Queen's Ships under Elizabeth I, was knighted in 1619. He entered Parliament in 1621 as member for Denbighshire, and represented Flintshire in the Parliaments of 1624 and 1625, Great Bedwyn in 1628-9. During the Personal Rule of Charles I, he was a member of several Royal Commissions, and amassed a substantial income: he had inherited from his father a share in the duties levied on coal from Newcastle, said to bring in £1,500 a year, and held the keepership of several Royal forests, all lucrative sinecures. (At one period he was Surveyor of Windsor Great Park.)
Trevor represented the Cornish borough of Grampound in the Long Parliament, having connections with Cornwall through his mother, a Trevanion. Taking the parliamentary side during the Civil War, he was sufficiently supportive of the trial of the King to survive Pride's Purge and sit in the Rump. He seems to have been accepted as the spokesman for North Wales in many of the administrative committees that took over the country after the overthrow of the Monarchy, being twice elected to the Council of State, and also serving on the Committee of Both Kingdoms from 1648. However, he was not a member of the smaller council established after Cromwell assumed the Protectorate in 1653. In the Second Protectorate Parliament, Trevor was MP for Arundel, and was one of those advocating the offer of the Crown to Cromwell (to whom he was related by his son's marriage to John Hampden's daughter, Ruth). He sat in the Third for Steyning.
Although he resumed his seat in the restored Rump after Richard Cromwell's fall, he was an early supporter of the Restoration of Charles II, which ensured that he suffered no penalties for his earlier political loyalties after the King returned, being granted a royal pardon on 24 July 1660. However, he had invested much of his fortune during the Commonwealth in buying up lands confiscated from convicted Royalists, and suffered considerable loss as a result.
Trevor's son, also called Sir John Trevor (1626–1672), was an MP with his father during the Commonwealth, and after the Restoration rose to become Secretary of State in 1668.