JOHN, 1st marquess of Hamilton (c. 1542-1604), third son of James Hamilton, 2nd earl of Arran (q.v.) and duke of Chatel lerault, was given the abbey of Arbroath in 1551. In politics he was largely under the influence of his unscrupulous younger brother Claud, afterwards Baron Paisley (see HAMILTON) . At first hostile to Mary, they later became her devoted partisans. Claud met Mary on her escape from Lochleven and escorted her to Hamilton palace. John appears to have been in France in 1568 when the battle of Langside was fought, and it was probably Claud who commanded Mary's vanguard in the battle. With others of the queen's party they were forfeited by the parliament and sought their revenge on the regent Murray. Although the Hamiltons disavowed all connection with Murray's murderer, James Hamilton of Bothwellhaugh, he had been provided with horse and weapons by the abbot of Arbroath, and it was at Hamil ton that he sought refuge after the deed. Their uncle, Archbishop Hamilton, was hanged at Stirling in 1571 for alleged complicity in the murder of Darnley, and is said to have admitted that he was a party to the murder of Murray. At the pacification of Perth in 1573 the Hamiltons abandoned Mary's cause. On the uncertain evidence extracted from the assassin by torture, the Hamiltons had been credited with a share in the murder of the regent Lennox in 1571. In 1579 proceedings against them for these two crimes were resumed, and when they escaped to England their lands and titles were seized by their enemies, James Stewart becoming earl of Arran. John Hamilton presently dissociated himself from the policy of his brother Claud, who continued to plot for Spanish intervention on behalf of Mary. With other Scottish exiles he crossed the border in 1585 and marched on Stirling; he was admitted on Nov. 4, and formally reconciled with James VI., with whom he was thenceforward on the friendliest terms. He was created marquess of Hamilton and Lord Evan in 1599, and died on April 6, 1604.
His eldest surviving son JAMES, 2nd marquess of Hamilton (c. 1589-1625), was created baron of Innerdale and earl of Cambridge in the peerage of England in 1619, and these honours descended to his son James, who in 1643 was created duke of Hamilton (q.v.). William, 2nd duke of Hamilton (1616-165T), succeeded to the dukedom on his brother's execution in 1649. He was created earl of Lanark in 1639, and in the next year became secretary of state in Scotland. Arrested at Oxford by the king's orders in 1643 for "concurrence" with Hamilton, he escaped, and was temporarily reconciled with the Presbyterian party. Sent by the Scottish committee of estates to treat with Charles I. at New castle in 1646, he sought in vain to persuade the king to consent to the establishment of Presbyterianism in England. On Sept. 26, 1647 he signed on behalf of the Scots the treaty with Charles known as the "Engagement" at Carisbrooke Castle, and helped to organize the second Civil War. In 1648 he fled to Holland; he returned to Scotland with Prince Charles in 165o, and joined in the Scottish invasion of England. He died on Sept. 12, 1651 from wounds received at Worcester. He left no male heirs, and the title devolved on the 1st duke's eldest surviving daughter Anne, duchess of Hamilton in her own right.
Anne married in 1656 William Douglas, earl of Selkirk (163 1694), who was created duke of Hamilton in 166o on his wife's petition, receiving also several of the other Hamilton peerages, but for his life only. He resisted Lauderdale's measures in Scot land, and was dismissed from the privy council in 1676. He presided over the convention of Edinburgh which offered the Scottish crown to William and in March 1689. He died at Holyrood on April 18, 1694. His wife survived until 1716.