The Pomeranian War was a theatre of the Seven Years' War. The term is used to describe the fighting between Sweden and Prussia between 1757 and 1762 in Swedish Pomerania, Prussian Pomerania, northern Brandenburg and eastern Mecklenburg-Schwerin. The war was formally ended on 22 May 1762 by the Peace of Hamburg between Prussia, Mecklenburg and Sweden. The hopes of the Swedish Hats party to recover territories lost to Prussia in 1720 were thwarted, and the unpopular and costly war contributed to their subsequent downfall.