A Prince-Bishop is a bishop who is a territorial Prince of the Church on account of one or more secular principalities, usually pre-existent titles of nobility held concurrently with their inherent clerical office. If the see is an archbishopric, the correct term is prince-archbishop; the equivalent in the regular clergy is a prince-abbot.
In the West, with the decline of imperial power from the 4th century onwards in the face of the barbarian invasions, sometimes Christian bishops of cities took the place of the Roman commander, made secular decisions for the city and led his own troops when necessary. Later relations between a prince-bishop and the burghers were not invariably cordial. As cities demanded charters from emperors or kings and declared themselves independent of the secular territorial magnates, friction intensified between burghers and bishops.
In the Byzantine Empire, the still autocratic Emperors passed general legal measures assigning all bishops certain rights and duties in the secular administration of their dioceses, but that was part of a caesaropapist development putting the Eastern Church in the service of the Empire, with its Ecumenical Patriarch almost reduced to the Emperor's minister of religious affairs. The Russian empire went even further, abolishing its own patriarchy and placing the church under direct control of the secular government.
The German term Hochstift was often used to denote the form of secular authority held by bishops ruling a prince-bishopric.
Holy Roman Empire
Bishops had been involved in the government of the Frankish realm and subsequent Carolingian empire frequently as the clerical member of a duo of envoys styled Missus dominicus, but that was an individual mandate, not attached to the see.
Prince-bishoprics were most common in the feudally fragmented Holy Roman Empire, where many were formally awarded the rank of Reichsfürst ("Prince of the Empire"), granting them representation in the Reichstag (imperial Diet).
They were finally dissolved in most countries by Napoleon Bonaparte, with the downfall of the Holy Roman Emperor in 1806. However in some countries outside of French control, such as Austria and Prussia the institution continued, and in some cases was revived; a new, titular type arose.
In what is now the Federal Republic of Germany
No less than three of the (originally only seven) Prince-electors, the highest order of Reichsfürsten (comparable in rank with the French pairs), were Prince-archbishops, each holding the title of Archchancellor (the only archoffice amongst them) for a part of the Empire; given the higher importance of an electorate, their principalities were known as Kurfürstentum ('electoral principality') rather than prince-archbishoprics:
- Elector-Archbishopric of Cologne (Köln)
- Elector-Archbishopric of Mainz (Mayence, Mentz)
- Elector-Archbishopric of Trier (Trier)
Other prince-archbishoprics were
- Prince-Archbishopric of Magdeburg
- Prince-Archbishopric of Bremen; continued by Lutheran administrators after Reformation in 1566 until 1645/1648
Other prince-bishoprics in present Germany were those of:
- Brandenburg; continued by Lutheran administrators after Reformation in 1520 until 1571
- Constance (Konstanz)
- Freising, later München-Freising
- Fulda, until 5 October 1752 a Reichsabtei
- Havelberg; continued by Lutheran administrators after Reformation in 1548 until 1598
- Lebus, seated in Fürstenwalde; continued by Lutheran administrators after Reformation in 1550 until 1598
- Lübeck; continued by Lutheran administrators after Reformation in 1535 until 1803
- Osnabrück, exchanged between Catholic and Protestant incumbents after the Thirty Years' War, an example of post-Reformation denaturation
- Regensburg (Ratisbon)
- Speyer (Spires)
- Verden; continued by Lutheran administrators after Reformation until 1645/1648
Furthermore there were prince-bishoprics in neighbouring regions, then considered part of Germany (the Holy Roman Empire minus all other realms within the empire), notably in the former central kingdom of Lotharingia, now in France's region Alsace-Lorraine:
- Straßburg (Strasbourg in French)
- the so-called three Lorrain bishoprics:
- Basel. Most of the former Fürstbistum Basel is now in Switzerland.
In what is now Austria
- The Archbishopric of Salzburg was and remains the Catholic metropolitan, with primatial title; in 1803 its large temporal territory was raised to the status of electorate, but also secularised as a duchy.
Furthermore, among of its suffragans:
- the prince-bishop of Gurk, in Carinthia
- the prince-bishop of St.Andrä/Lavant, in Styria
- the prince-bishop of Seckau, also in Styria, later shifting see to Graz
In what is now Switzerland
- The establishment of the Bishopric of Sion, or rather Sitten in German, is a classic example of unified secular and diocesan authority.
- the prince-bishop of Geneva (Genève in French, Genf in German), lost his territory between 1526 and 1539
- the bishop of Lausanne, lost its territory 1526
- the prince-bishop of Chur
- the prince-bishop of Basel, originally ruling the territory of the contemporary Swiss cantons of Basel and Jura, after the reformation in Basel only Jura an part of Basel-Contry
In what are now the Low Countries
- Liège in present Belgium; Dutch: Luik, German: Lüttich
- Cambrai (Kamerijk in Dutch; an archiocese 1559-1802), now in France, was a medium-size prince-bishopric in the Holy Roman Empire, which in 1007, St. Henry II invested with authority over the countship of Cambrésis, remaining a real prince-(arch)bishopric until under Louis XIV it became French in 1678, and ecclesiastically covered long about all the western part of Belgium (the rest was under Liège).
- The Bishopric of Utrecht had a surrounding Sticht (Stift), until its conversion into a temporal lordship in 1527 (later became the only Dutch archbishopric), but also a far larger Oberstift ('Opper Stift'), in Germany proper, also until secularized and broke up (mainly lordships of Overijssel, 1528 and of Drenthe, 1538) , only later raised to metropolitan rank
- Those three were all (at least originally) suffragans of the elector (prince-archbishop) of Cologne
In present Italy
- the prince-archbishopric of the patriarch of Aquileia, known because of its superior ecclesiastical rank as patriarchate
- the bishop (and count) of Brescia
- the bishop of Brixen (Bressanone in Italian), until 1964
- the bishop of Trent (Trento in Italian, Trient in German)
- the bishop of Triest held the homonymous countship (it had earlier been a duchy)
In the East
- The prince-bishop of Cammin (in Polish: Kamień Pomorski)
- In Silesia, since bishop Preczlaus of Pogarell (1341-1376) bought the Duchy of Grottkau from Duke Boleslaw of Brieg and added it to the episcopal territory of the Fürstentum von Neiße, the Bishops of Breslau were Fürst (Prince) of Neiße and Herzog (Duke) of Grottkau, and took precedence over the other Silesian rulers
- In the non-Slavic Baltic region of Ermland (in Polish: Warmia), the Prince-Bishopric of Ermland (in German: Hochstift Ermland; in Polish: Biskupie Księstwo Warmińskie), established in 1243, became a sovereign imperial estate since 1251, in 1454 incorporated into the Kingdom of Poland (recognised by the prince-bishop only in 1464) as a part of (West) Royal Prussia, in 1466 under direct Polish crown sovereignty, 1479 re-established as autonomous prince-bishopric under the Polish crown, in 1772 abolished at Prussian annexation (First partition of the Polish-Lithuanian Commonwealth). It remained a purely religious diocese of Ermland inside Prussia and Germany (covering East Prussia and West Prussia largely) until its 1945 dissution when East Prussia fell to Poland and the Soviet Union.
The career of Albert of Buxhoeveden and his brother Herman exemplify the double nature of power, especially on the marches of Europe, where Roman Catholicism was pushed aggressively to the East. In the early 13th century, the time of the Third Crusade, Albert's fleet of ships and a thousand crusaders began the Christianization of the Eastern Baltic region, with the blessing of Pope Innocent III, his uncle the Archbishop of Hamburg-Bremen, and of King Philip of the Holy Roman Empire, who created the former canon of Bremen a Prince of the Holy Roman Empire (1207) and Livonia (Latvia and part of Estonia) as a fief. The Prince built his own cathedral at Riga, the city which he founded.
- The Czech bishopric (later Metropolitan) of Olmütz, as a vassal principality of the Bohemian crown, was the peer of the margraviate of Moravia, and from 1365 its prince-bishop was 'Count of the Bohemian Chapel', i.e. first court chaplain, who was to accompany the Monarch on his frequent travels.
Former Ottoman territories
The vladikas of Cetinje, who took the place of the earlier secular (Grand) Voivodes in 1516 in the unique position of Slavonic, Orthodox prince-bishops under Ottoman (i.e. Islamic) suzerainty, actually became the secularized, hereditary princes and ultimately kings of Montenegro in 1852, as reflected in their styles: first Vladika i upravitelj Crne Gore i Brde "Vladika [bishop] and Ruler of Montenegro and Brda"; (b) from 13 March 1852 (New Style): Po Bozjoj milosti knjaz i gospodar Crne Gore i Brde "By the grace of God Prince and Sovereign of Montenegro and Brda"; (c) from 28 August 1910 (New Style): Po Bozjoj milosti kralj i gospodar Crne Gore "By the grace of God, King and Sovereign of Montenegro".
The Bishops of Durham were also territorial Prince Bishops, with the extraordinary secular rank of Earl palatine, for it was their duty not only to be head of the large diocese, but also to help protect the Kingdom against the Scottish threat from the north. The title survived the union of England and Scotland into the Kingdom of Great Britain in 1707 until 1836.
However, a number of French Bishops did hold a noble title, with a tiny territory usually about their seat; it was often a princely title, especially Count. Indeed, six of the original Pairies (the royal vassals awarded with the highest precedence at Court) were episcopal: the Archbishop of Reims and five other Bishops (suffragans to Reims, except the Bishop of Langres); the three highest ones held a ducal title and the others a comital title.
Beyond Catholic feudalism
Even when the true prince-(arch)bishoprics disappeared from the map of Europe as it was redrawn by Napoleon I Bonaparte (who caused the end of the Holy Roman Empire) and the Congress of Vienna after his defeat, the title found a new, titular use. In the Habsburg dynasty's "new" empire, the Danubian Double Monarchy Austria-Hungary, reduced to the parts south of Prussia's (German) sphere of dominance that would become the (largely Protestant) German Empire, actual territorial power was no longer held by the bishops, but the status of Fürst(erz)bischof was maintained, and could be given a similar political role in the more modern, almost standardized Cisleithanian provincial level, the Kronland 'crown land', as ex officio members of its Landtag, the representative and legislative assembly, often with Virilstimme, while other bishops could collectively be represented as a 'prelates bench' (an elected Kurie).
The Emperors of Austria now bestowed the title upon Bishops even without any feudal principality, but as a princely style and rank (as had been usual for centuries with secular noble titles of peerage ranks) awarded to episcopal sees, carrying the privilege of a seat in the estates, e.g. for the bishop of Laibach (as a consolation prize for the see's loss of metropolitan rank to Graz).
The ultimate Prince Bishop is the Bishop of Rome, i.e. the Pope, universal head (Supreme Pontiff) of the Roman Catholic Church. His claims to territorial power were bolstered by the fraudulent early-Medieval document Donation of Constantine, and the authentic Donation of Pepin, establishing the Patrimonium Petri which was further extended as the powerful Papal States. Pope Pius IX was the last of the true, sovereign Prince-Bishops, divested of territorial powers when the Papacy was forced to surrender the rule of Rome in 1870 to the reunited kingdom of Italy, which was supported by liberal-nationalists. The Pope was however made Head of state again of the specially created Vatican City, a small enclave in Rome, by the (later favorably amended) Lateran Treaties with Benito Mussolini's Fascist Italy.
The Spanish Catalonian Bishop of Urgell, who no longer has any secular rights in Spain, still is one of the two co-princes of Andorra, along with the Head of State (presently President of the Republic) of France.
- Catholic Encyclopaedia passim
- The Prince-Bishop of Münster
- Albert of Buxhoeveden, Prince-Bishop of Livonia
- Heraldica.org - here French peerage
- Westermann, Großer Atlas zur Weltgeschichte (in German)
- WorldStatesmen search under each present country