Countess Amalie Sophie Marianne von Wallmoden-Gimborn, Countess of Yarmouth, born Amalie von Wendt was the principal mistress of King George II from the mid-1730s until his death in 1760. Born into a prominent family in the Electorate of Hanover, and married into another, in 1740 she became a naturalised subject of Great Britain and was granted a peerage for life, with the title of "Countess of Yarmouth", becoming the last royal mistress to be so honoured. She remained in England until the death in 1760 of King George II, who is believed to have fathered her second son, Johann Ludwig, Reichsgraf von Wallmoden-Gimborn. She returned to Hanover for the rest of her life, surviving the king for nearly five years.

George II was King of Great Britain and Ireland, Duke of Brunswick-Lüneburg (Hanover) and a prince-elector of the Holy Roman Empire from 11 June 1727 (O.S.) until his death in 1760.