The Treaty of Berlin was concluded on 2 May 1715, during the Great Northern War. It allied George I of Great Britain, as Elector of Hanover, with Denmark-Norway, in return for the cession to Hanover of the Swedish dominion of Bremen-Verden, which was occupied by Denmark.[1] With the 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]