The town was incorporated into the Duchy of Lower Lotharingia, which became part of the Duchy of Brabant at the end of the 12th century. Despite its proximity to Liège, the territory of Herstal did not become part of the Prince-Bishopric of Liège until 1740, when the prince-bishop Georges-Louis de Berghes bought it from Frederick II of Prussia.[3] By that time, the town was mainly known for its able craftsmen: ceramists, blacksmiths, and clockmakers.