Sarah Lennox (18 September 1705 – 25 August 1751), was born Sarah Cadogan as the eldest daughter of William Cadogan (since 1716 1st Baron Cadogan of Reading and since 1722 1st Earl Cadogan) and his wife Margaret Cecilia Munter. On 4 December 1719, she married Charles Lennox, Earl of March at The Hague and in 1723, Charles succeeded to his father's title of Duke of Richmond, whereupon Sarah became Duchess of Richmond. Sarah was Lady of the Bedchamber to Queen Caroline from 1724 to 1737.