The principality ruled by the bishops of Liège was never part of the Seventeen Provinces or the Spanish and Austrian Southern Netherlands, but from the 16th century onwards its politics were strongly influenced by the dukes of Burgundy and later the Habsburgs.

The most important cities (bonnes villes) of the bishopric were: Liège, Beringen, Bilzen, Borgloon, Bree, Châtelet, Ciney, Couvin, Dinant, Fosses-la-Ville, Hamont, Hasselt, Herk-de-Stad, Huy, Maaseik, Peer, Sint-Truiden, Stokkem, Thuin, Tongeren, Verviers, Visé and Waremme.

The city of Maastricht fell under the joint jurisdiction of the prince-bishop of Liège and the duke of Brabant (later the States-General of the United Provinces).

This situation continued until the French Revolution, and throughout that period of nearly eight centuries the Prince-Bishopric of Liège succeeded in maintaining a level of autonomy, though it remained under the emperor.

This virtual independence was owed largely to the ability of its bishops, who on several occasions played an important part in international politics, being strategically positioned between France and Germany.

Subsequent bishops, Balderic of Looz (1008–1018), Wolbodo (1018–1021), Durandus (1021–1025), Reginard (1025–1038), Nitard (1038–1042), the learned Wazo, and Theoduin (1048–1075), valiantly sustained the heritage of Notger.

The schools formed many brilliant scholars, and gave the Catholic Church popes Stephen IX and Nicholas II.

The diocese also supplied the University of Paris with a number of important doctors — William of Saint-Thierry, Gerard of Liège and Godfrey of Fontaines.

The episcopate of Raoul of Zachringen was marked by the preaching of the reformer Lambert le Bègue, who is credited with founding the Béguines.

In the reign of Robert of Thourotte (1240–1246), Saint Juliana — a nun of Cornillon Abbey — was led by certain visions to the project of having a feast established in honour of the Blessed Sacrament.

The completion of the work was left to a former prior of the Dominicans in Liège, Hugh of Saint-Cher, who returned to the city as papal legate.

John of Troyes, who, after having been archdeacon at Liège, was elected pope as Urban IV, encouraged the observance of the feast of Corpus Christi in the whole Church.

The Peace of Fexhe, signed in 1316 during the reign of Adolph II de la Marck (1313–1344), regulated the relations between the prince-bishop and his subjects.

The importance of the prince-bishopric to Habsburg military logistics in the Eighty Years War prompted Spanish intervention foiling a Dutch invasion in 1595.

Their frequent absences gave free scope for those feuds of the Chiroux and the Grignoux to which Maximilian Henry of Bavaria (archbishop of Cologne, 1650–1688) put a stop by the Edict of 1681.