The County of Bar, from 1354 the Duchy of Bar, was a principality of the Holy Roman Empire including the pays de Barrois and fixated on the city of Bar-le-Duc. Some portion of the area—the supposed Barrois mouvant—turned into a fief of the Kingdom of France in 1301, while the Barrois non-mouvant remained a piece of the Empire. From 1480 it was united to the supreme Duchy of Lorraine. Both royal Bar and Lorraine were surrendered to France in 1738. With the demise of the last duke, Stanislaus Leszczynski, in 1766 the duchy escheated to the French crown.