MAITLAND, JOHN (1614-1682), earl and afterwards duke of Lauderdale in the peerage of Scotland, was a great-grandson of Sir RICHARD MAITLAND (2.v.). In early life a Presbyterian, he attended the Westminster Assembly in 1643 as an elder of the Church of Scotland ; and he was a party to the surrender of Charles I. to the English army in 1645. Soon afterwards, changing his politics, he became a zealous supporter of the royal cause, and promoter of the Engagement for raising forces for the king's rescue. He was taken prisoner at the battle of Worcester; and, on being set at liberty in 1660, he repaired to the Hague and accompanied Charles IL to Scotland. From 1663 he was virtually ruler of Scotland, - at first moderate in his counsels, but afterwards severe in his measures against the Covenanters. In 1672 he was made duke of Lauderdale and a Knight of the Garter ; and he had also an English peerage conferred on him (with the title of earl of Guildford) in 1674. One of the administrative council known as the "Cabal," he eventually fell into disgrace, and died in 1682. His dukedom and English honours expired with him ; the earldom of Lauderdale passed to his brother Charles, and is still in possession of his descendants. The voluminous correspondence of Lauderdale, which is still extant, shows that, in addition to a remarkable power over men of all classes, great watchfulness and resolution, and very clear ideas of what was needed to keep Scotland peaceful and in a state of usefulness for further ends, he was possessed of no slight learning.