Prince-Bishop was the title given bishops who held secular powers, beside their inherent clerical power. In the West, from the 4th century onwards, the Christian bishop of cities took the place of the Roman commander, made the secular decisions for the city and led his own troops when necessary. Prince-bishoprics were not uncommon in the Holy Roman Empire, until they were finally dissolved by Napoleon, with the downfall of the old Empire and Holy Roman Emperor in 1806.

The establishment of the Bishopric of Sion is a classic example of unified secular and diocesan authority.

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. At the opening of the 13th century, the time of the Third Crusade, Albert, with a 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 and Bremen, and of King Philipp of the Holy Roman Empire, who created the former canon of Bremen 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 that he founded.

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. This development, which characterized the rise of towns in the early Middle Ages, was re-enacted at a later date, when the Prince-Bishop of Münster, Christoph Bernhard von Galen, demanded the submission of this free Imperial city, and besieged it with troops— in 1657!. The Dutch were poised at the border, ready to defend the privileges of the old city. The city requested a Dutch garrison; the Dutch Republic hoped for negotiations; Emperor Leopold I's envoy was turned away by the "cannon-bishop". In May 1661, the city of Münster surrendered to its bishop, who constructed a citadel, the Paulsburg within the city's walls.

The chief of the Prince Bishops was the Bishop of Rome, whose claims to territorial power were bolstered by the fraudulent document called the Donation of Constantine. He was the last of the prince bishops and was divested of territorial powers when the Papacy gave up the rule of Rome in 1870. The Pope remains head of state of the Vatican City.

In England the famous Bishops of Durham were also styled until 1836 as Prince Bishops, for it was their duty not only to be head of the diocese, but also to 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.

The Bishops of Durham founded the University of Durham, one of the most prestigious and the third oldest university in England after the Universities of Oxford and Cambridge.

The Bishop of Urgell is one of the two co-princes of Andorra, along with the President of France.

External links

• The Prince-Bishop of Münster
• Albert of Buxhoeveden, Prince-Bishop of Livonia