Peter I of Bar, Lord of Pierrefort

Peter I of Bar (c. 1272–1347), lord of Pierrefort, was a younger son of Count Theobald II and founder of the Pierrefort branch of his house. He married Joan of Vienne, and his children included Henry and Hugh.

After Count Henry IV died in 1344, Peter and a kinsman claimed seats on the regency council for the young Edward II, but the regent Yolande of Flanders, allied with King Philip VI, confined them to minor roles. Peter died on 30 November 1347.