The Treaty of Berlin was concluded on 2 May 1715, during the Great Northern War. It formalized an alliance between George I of Great Britain (in his role as Elector of Hanover) and Denmark-Norway, in return for the cession of the Swedish dominion of Bremen-Verden to Hanover, which had been occupied by Denmark.[1] With this treaty, Denmark and Hanover joined the Russo-Prussian coalition that had been established by the Treaty of Schwedt.[2] Denmark was assured the gain of yet-to-be-conquered Stralsund.[2]