Tsar Peter the Great, is formally proclaimed the title of "Emperor of All Russia" after Russia's victory in the Great Northern War. The title was bestowed upon him by the Governing Senate and Synod in September 1721, and was accepted by him in November 2, 1721, formally transforming the Tsardom of Russia into the Russian Empire.
During the Great Northern War, Russia fought against the Swedish Empire led by King Charles XII, while Russia, under Tsar Peter the Great, led an anti-Swedish coalition that also included Denmark-Norway, Saxony, and eventually Poland.