Sacerdotal state

A sacerdotal state is a state whose head is also an ecclesiastical leader designated by a religious body. An example of this kind of state is the Vatican City, whose head of state is the pope of the Catholic Church since the eighth century. Andorra operates under a semi-sacerdotal system, as one of its co-heads of state is the bishop of Urgell, while the other is the president of France. However unlike the Vatican, the co-princes of Andorra are not closely involved in the government.

In the past it was common for bishops to assume civil as well as clerical power and rule as prince-bishops. This was common in the Holy Roman Empire, where three of the seven imperial electors were prince-archbishops (Trier, Mainz and Cologne). After the Peace of Westphalia certain prince-bishoprics became bi-confessional and alternated between Catholic bishops and Protestant administrators.