John, 9th Earl of Rothes (c.1679-1722), succeeded to his mother's titles in 1700. A fervent supporter of the Anglo-Scottish Union, he entered politics early, and over an eminent career held, amongst others, the offices of: a Representative Peer (1708-10 and 1715-22); Lord Privy Seal; Vice-Admiral of Scotland; Captain and Governor of Stirling Castle; and Lord Lieutenant of Fife, Kinross and Aberdeen. He married Jean, daughter of the Marquess of Tweeddale, on 29th April 1697, by whom he had six sons.