Robert Maxwell, 1st Earl of Nithsdale (after 1586 – May 1646), was a Scottish nobleman. He succeeded his brother as 10th Lord Maxwell in 1613,[2] and was created Earl of Nithsdale in 1620. General of Scots in Danish-Norwegian service during the Thirty Years' War. A loyal supporter of Charles I and a prominent Catholic, he lost his titles and estates in 1645, dying on the Isle of Man in 1646.