Mary Anne Clarke (born Mary Anne Thompson 3 April 1776 – 21 June 1852) was the mistress of Prince Frederick, Duke of York and Albany. Their relationship began in 1803, while he was Commander-in-Chief of the army. Later in 1809, she wrote her memoirs which were published. She was the subject of a portrait by Adam Buck, and a caricature by Isaac Cruikshank; ten days after the latter's publication, the Duke resigned from his post as Commander of the British Army. In 1811, she commissioned Irish-born sculptor Lawrence Gahagan to sculpt a marble bust of her; this is now housed in the National Portrait Gallery, London.Through her daughter who married Louis-Mathurin Busson du Maurier, Clarke was the ancestress of author Daphne Du Maurier, who wrote the novel Mary Anne about her life.