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:

• Bishop of Bremen from 787 to 845
• Archbishop of Hamburg and Bishop of Bremen in personal union (colloquially also Archbishop of Hamburg-Bremen) from 848 to 1072
• Archbishop of Bremen (colloquially also Archbishop of Hamburg-Bremen) from 1072 to 1179
• Prince-Archbishop of Bremen from 1180 to 1566, paralleled by the de facto rule of Catholic Administrators from 1316 to 1327 and again 1348 to 1360
• Administrator of the Prince-Archbishopric of Bremen 1316 to 1327, 1348 to 1360, and again 1568 to 1645. Either simply de facto replacing the Prince-Archbishop or lacking canon-law prerequisites, the incumbent of the see would officially only hold the title administrator (but nevertheless colloquially referred to as Prince-Archbishop). Between 1568 and 1645 all administrators were Lutherans, while else they were Roman Catholics.
• The last, but only provisional incumbent of the See, Francis of Wartenberg, therefore bore the title Vicar Apostolic (1645–1648)

Roman Catholic Bishops of Bremen (787–845)
Episcopate	Picture	Name	Birth and death with places	Reason for end of office	Notes
787–789		Willehad also Willehadus or Willihad	Northumbria *ca. 745 – 8 November 789*, Blexen, today a part of Nordenham	death	Saint
789–805		sede vacante
805–838		Willerich also Willeric, Wilrich, Wilderic	*unknown – 4 May? 838*	death
838–845		Leuderich also Leutrich in High German	*unknown – 24 August 845*	death
845–847		sede vacante

Roman Catholic Archbishops of Hamburg in personal union Bishops of Bremen (848–1072)
Episcopate	Picture	Name	Birth and death with places	Reason for end of office	Notes
847–865		Ansgar also Anschar in Low Saxon, Oskar in Scandinavian languages	Corbie *796 or 8 September 801? – 3 February 865* Bremen	death	in personal union archbishop of Hamburg 831–865, Apostle of the North Saint
865–888		Rimbert of Turholt also Rembert or Rembart	near Turholt? in Flanders *830 – 11 June 888*, Bremen	death	second Apostle of the North Saint
888–909		Adalgar also Adelger	*unknown – 9 May 909* Bremen	death	Saint
*909–916		Hoger also Huggar	*unknown – 20 December 916*	death
917–918		Reginwart	*unknown – 1 October 918*	death
918–936		Unni	*unknown – 17 September 936*, Birka	death	third Apostle of the North Saint
936–988		Adaldag also Adelgis or Adelger	*ca. 900 – 28 April 988*	death
988–1013		Liawizo I also Libizo, Libentius I in Latin	Burgundy or Raetia *unknown – 4 January 1013*	death	Apostle of the Slavs uncle of Liawizo II Saint
1013–1029		Unwan, Count Palatine of Saxony also Unwin (House of Immeding)	*unknown – 27 January 1029* Bremen	death
1029–1032		Liawizo II also Libentius II	*unknown – 24 August 1032*	death	nephew of Liawizo I
1032–1035		Hermann	*unknown – 19 September 1035*	death
1035–1043		Adalbrand of Bremen (in High German) also Alebrand in Low Saxon, or Bezelin, Becelin, Bencelin	*unknown – 15 April 1043	death
1043–1072		Adalbert, Count Palatine of Saxony as Albert I	Goseck *ca. 1000 – 16/25 March 1072* Goslar	death

Roman Catholic Archbishops of Bremen (1072–1179)
Episcopate	Picture	Name	Birth and death with places	Reason for end of office	Notes
1072–1101		Liemar	*unknown – 16 May 1101* Bremen	death
1101–1104		Humbert, Archbishop of Bremen	*unknown – 10 November 1104*	death	During his term, the whole of Scandinavia was removed from the archdiocese of Bremen to form its own archdiocese, seated in Lund
1104–1123		Frederick I	*unknown – 29 January 1123*	death
1123–1148		Adalbero, Archbishop of Bremen as Adalbert II	*unknown – 5 August 1148*	death
1148–1168		Hartwig, Count of Stade as Hartwig I (House of Udonids)	*before 1124 – 11 October 1168* Bremen	death	brother of Liutgard of Stade, Queen consort of Denmark
1168, episcopate claimed		Siegfried of Anhalt (House of Ascania)	*ca. 1132 – 24 October 1184*	inhibited by Guelphic partisans	Archbishop Elect of Bremen, elected by the Chapter and preferred by his father Albert the Bear, Bishop of Brandenburg 1173–1179, became Prince-Archbishop of Bremen in 1180
1168–1178		Baldwin I also Balduin	*unknown – 18 June 1178* Bremen	dismissed by Pope Alexander III, ensued by Baldwin's death	preferred candidate of Guelphic Henry III, the Lion, imposed by Frederick I Barbarossa against the Chapter's candidate Siegfried
1178–1179		Bert(h)old also Bertram	*unknown – 6 April 1212*	dismissal	never papally confirmed, Prince-Bishop of Metz 1180–1212

Roman Catholic Prince-Archbishops of Bremen (1180–1316)
Reign and episcopate	Picture	Name	Birth and death with places	Reason for end of office	Notes
1180–1184		Siegfried of Anhalt (House of Ascania)	*ca. 1132 – 24 October 1184*	death	before bishop of Brandenburg 1173–1180
1184–1185		rule by the Chapter due to sede vacante
1185–1190		Hartwig of Uthlede as Hartwig II, also Wilrich	*unknown – 3 November 1207*	dismissal	deposed as prince by Henry VI, never papally dismissed as archbishop
1190–1192		rule by the Chapter due to sede vacante			Chapter disregarded Hartwig II's persisting papal acceptance as archbishop
1192		Valdemar of Denmark also Waldemar (House of Estridsen)	*1157/1158 – April 1235 or 1236* Cîteaux	held in Danish captivity 1193–1206	imprisoned by Canute VI of Denmark, also bishop of Schleswig 1182–1208
1192–1207		Hartwig of Uthlede as Hartwig II, also Wilrich	*unknown – 3 November 1207*	death	de facto reaccepted by the Chapter, since Valdemar stayed imprisoned
1207–1210		Burchard, Count of Stumpenhusen as Burchard I		resignation	temporarily accepted as anti-archbishop only in Hamburg, nephew of Gerard I
1208–1217		Valdemar of Denmark (House of Estridsen)	*1157/1158 – April 1235 or 1236* Cîteaux	dismissal	only in Bremen accepted as imperially invested prince, papally dismissed and banned
1210–1219		Gerard of Oldenburg-Wildeshausen as Gerard I (House of Oldenburg)	*unknown – 14 August 1219*	death	uncle of Burchard of Stumpenhusen, also prince-bishop of Osnabrück 1190–1216
1219–1258		Gerhard of Lippe also Gerard II (House of Lippe)	*ca. 1190 – 27 July or 28 August 1258* Vörde	death	son of Bernard II, Lord of Lippe, titled Bishop of Hamburg in the diocesan territory right of the Elbe, and Archbishop of Bremen left of the Elbe
1258–1273		Hildebold, Count of Wunstorf	*unknown – 11 October 1273*	death	temporarily rivalled by anti-archbishop Gerhard of Lippe, accepted only in Hamburg, a grandnephew of Gerard II and supported by his uncle Simon [de], Gerard II's coadjutor
1273–1274		rule by the Chapter due to sede vacante
1274–1306		Gilbert of Brunckhorst also Gis(el)bert of Bronchorst (House of Bronckhorst)	*unknown – 18 November 1306* Vörde	death
1306–1307		Henry of Goltern also of Golthorn, as Henry I	*unknown – 9 April 1307*	death	died before papal confirmation
1307, only elect		Florence, Count of Brunckhorst also Florentius, Floris, also of Bronchorst (House of Bronckhorst)	*unknown – 1308* Avignon	death	died before papal confirmation, counter-candidate to the next
1307, only elect		Bernard of Wölpe (Counts of Wölpe)	*ca. 1230/1240 – 17 September 1310*	death	never papally confirmed, counter-candidate to the former
1307–1310		rule by the Chapter due to sede vacante
1310–1316 (1327)		Jens Grand the Firebug as John I, (House of Hvide)	*ca. 1260 – 30 May 1327* Avignon	declared mentally insane by the Chapter on 19 May 1316 and dismissed, however, in 1318 papally recognised again till his death	lacking the capitular elective mandate, only papally appointed, before Archbishop of Lund 1289–1302, Prince-Archbishop of Riga 1304–1310

Lutheran Administrators of the Prince-Archbishopric of Bremen (1568–1645)
Reign	Picture	Name	Birth and death with places	Reason for end of office	Notes
1568–1585		Henry of Saxe-Lauenburg as Henry III (House of Ascania)	*1 November 1550 – 22 April 1585* Vörde	death	elected by the Chapter, dominated by Lutheran capitulars, imperially invested as prince, but never papally confirmed, also administrator of the prince-bishoprics of Osnabrück (1574–1585) and Paderborn (1577–1585)
1585–1589		rule by Chapter and Estates		majority of Administrator John Adolphus	custodianship for the minor administrator
1589–1596		John Adolphus of Schleswig-Holstein-Gottorp (House of Holstein-Gottorp)	* 27 February 1575 – 31 March 1616* Gottorp	resignation	also 1st Lutheran administrator of the Prince-Bishopric of Lübeck 1586–1607, after succeeding in 1590 his father as Duke regnant the Bremian Chapter enforced his resignation in favour of his brother
1596–1634		John Frederick of Schleswig-Holstein-Gottorp (House of Holstein-Gottorp)	Gottorp, *1 September 1579 – 3 September 1634*, Altkloster [nds]	death	also administrator of the Prince-Bishoprics of Lübeck (1607–1634) and Verden (1631–1634).
1634–1635		rule by Chapter and Estates due to sede vacante
1635–1645		Frederick of Denmark as Frederick II (House of Oldenburg)	Haderslev, *18 March 1609 – 9 February 1670*, Copenhagen	resignation by Second Peace of Brömsebro	also administrator of the Prince-Bishopric of Verden 1623–1629 and again 1634–1644, expelled from both sees by the Swedes

Roman Catholic Administrators and Vicars Apostolic, 1635/1645-Secularisation
Reign or vicariate	Picture	Name	Birth and death with places	Reason for end of office	Notes
1635, papal appointment, imperial investiture, lacking the capitular elective mandate		Leopold William of Austria as Administrator Leopold William (House of Habsburg)	Wiener Neustadt, *5 January 1614 – 20 November 1662*, Vienna	due to the Swedish occupation of the Prince-Archbishopric he never gained de facto power	Pope Urban VIII provided him as administrator (he lacked any clerical qualification to be bishop) of Bremen, his father Emperor Ferdinand II invested him with the princely regalia also administrator of the prince-bishoprics of Halberstadt (1628–48), Olomouc (1637–62), Passau (1625–62), Strasbourg (1626–62), and Wrocław (1656–62), as well as of the Prince-Archbishopric of Magdeburg (1631–38).
1645, papal appointment, lacking the capitular elective mandate		Francis of Wartenberg Vicar Apostolic Franz Wilhelm	Munich, *1 March 1593 – 1 December 1661*, Ratisbon	he never gained pastoral influence, let alone power as prince-archbishop due to the Swedish occupation of the prince-archbishopric	Pope Innocent X appointed him vicar apostolic, i.e. provisional head of see, also prince-bishop of Osnabrück (1625–1634 and again 1648–1661), of Ratisbon (1649–1661) and of Verden (1630–1631)
1645–1648		rule by the Swedish occupants due to sede vacante
After 15 May 1648		The Prince-Archbishopric was converted into a heritable monarchy, the Duchy of Bremen, first ruled in personal union by the Swedish crown. See List of dukes of Bremen (1648–1823).