The main cause for the Swedish intervention in the Seven Years' War was that the Hats faction then in power in Sweden believed Frederick II of Prussia would succumb to his many enemies, thus affording Sweden a risk-free opportunity to recapture its possessions in Pomerania that it had ceded to Prussia in 1720, towards the end of the Great Northern War. Angered and frightened by the attempted monarchial revolution of 1756, the Hats also wanted to cause Frederick's downfall and to humiliate and destroy the Swedish queen Louisa Ulrika of Prussia, Frederick's sister. The Hats faction was also encouraged to declare war by France, whose wishes were central to the Hats' actions.