The state was secularized by the Lutherans in 1558, and was given to Sweden by the Peace of Westphalia in 1648, which also fully recognized the secularization, and changed the territory's status from an Archbishopric to a Duchy. Following the Great Northern War, the Duchy was given to the Elector of Hanover in 1720, with whom it remained until the end of the Reich.
Archbishops of Bremen, 849-1558
Protestant Administrators of Bremen, 1558-1648