BREMEN ~ Archbishopric.
See also BREMEN ~ City-state
The city on the estuary of the Weser in northern Germany became the seat of a Bishop, a suffragan of Cologne, in 787. In 848 the diocese was merged with the recently created Archdiocese of Hamburg, which had been created to serve as a missionary Archbishopric for the northern peoples.
Hamburg having been twice sacked by the Danes, the Archbishop moved to Bremen, but the Archbishopric was often called Hamburg-Bremen well into the middle ages. The Archbishops were very powerful in German politics in the 11th century, but the creation of a separate Archbishopric at Lund in the Danish Kingdom diminished the power and prestige of Bremen.
The Archbishops acquired much of the land between the Weser and Elbe estuaries, principally as successors to the Counts of Stade. The last male of that family was Archbishop of Bremen, 1148-68. His intention to unite his County with the Archbishopric was thwarted however by Duke Henry the Lion, who grabbed the County for himself, and it was not until 1236, long after the fall of Henry, that the Archbishops got full control of Stade. They also leased the district around Wildeshausen, to the southwest of Bremen, 1270-1429.
The Archbishopric, which had been held by members of princely houses intermittently from 1361 and permanently from 1511, belonged to the Lower Saxon Circle from its formation in 1500. It went Protestant in the second half of the 16th century. Its last Protestant administrator, 1634-48, was Frederick, the second son and eventual heir of King Christian IV of Denmark.
It was not Denmark however that gained the lands of the Archbishopric in the settlement of 1648, but Sweden, which had occupied them since 1644. The impending loss to Sweden of the Duchy of Bremen, as the Prince-Archbishopric became, led the Emperor Ferdinand III to make the city of Bremen, long independent in practical terms, an Imperial Free City in 1646.
The Duchy of Bremen was seized by Denmark in 1712, but handed over to the Electorate of Hanover in 1715, and in 1719 was ceded by Sweden, with its neighbour, the former Bishopric of Verden, to Hanover, whose Elector had been King of Great Britain since 1714. The former Duchy was seized by Prussia in 1805, occupied by France in 1806, then annexed in 1810 until recovered by Hanover in 1813-15. In 1866 the old Archbishopric became part of Prussia, when Hanover was annexed by that Kingdom.