Charles Spencer, 3rd Duke of Marlborough, KG, PC (22 November 1706 – 20 October 1758), styled as The Honourable Charles Spencer between 1706 and 1729 and as The Earl of Sunderland between 1729 and 1733, was a British soldier, nobleman, and politician from the Spencer family. He briefly served as Lord Privy Seal in 1755. He led British forces during the Raid on St Malo in 1758.