Bishops of Bremen

This list records the bishops of the Roman Catholic diocese of Bremen (German: Bistum Bremen), supposedly a suffragan of the Archbishopric of Cologne, then of the bishops of Bremen, who were in personal union archbishops of Hamburg (simply titled Archbishops of Hamburg-Bremen), later simply titled archbishops of Bremen, since 1180 simultaneously officiating as rulers of princely rank (prince-archbishop) in the Prince-Archbishopric of Bremen (German: Erzstift Bremen; est. 1180 and secularised in 1648), a state of imperial immediacy within the Holy Roman Empire. Bremen and Hamburg were the seats of the chapters at Bremen Cathedral and Hamburg Concathedral, while the incumbents used to reside in their castle in Vörde since 1219.

Not all incumbents of the Bremian See were imperially invested princely power as Prince-Archbishops and not all were papally confirmed as bishops. In 1180 part of the Bremian diocesan territory and small parts of the neighbouring Diocese of Verden were disentangled from the Duchy of Saxony and became an own territory of imperial immediacy called Prince-Archbishopric of Bremen (German: Erzstift Bremen), a vassal of the Holy Roman Empire. The prince-archbishopric was an elective monarchy, with the monarch being the respective archbishop usually elected by the Bremian Chapters at Bremen Cathedral and Hamburg Concathedral, with the latter enfranchised to three capitular votes, and confirmed by the Holy See, or exceptionally only appointed by the Holy See. Papally confirmed archbishops were then invested by the emperor with the princely regalia, thus the title prince-archbishop. However, sometimes the respective incumbent of the see never gained a papal confirmation, but was still invested the princely regalia. Also the opposite occurred with a papally confirmed archbishop, never invested as prince. A number of incumbents, elected by the chapter, neither achieved papal confirmation nor imperial investiture, but as a matter of fact nevertheless de facto held the princely power. The respective incumbents of the see bore the following titles:

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