Complex sentence: The Dukedom of Gordon became extinct, but the Marquessate of Huntly (created in 1599) passed to his distant cousin the Earl of Aboyne while the Gordon estates passed to his nephew, Charles Gordon-Lennox, 5th Duke of Richmond.
Split into simpler sentences: The Dukedom of Gordon became extinct, but the Marquessate of Huntly (created in 1599) passed to his distant cousin the Earl of Aboyne. The Gordon estates passed to his nephew, Charles Lennox, 5th Duke of Richmond.