In the 12th century, the Archbishop of Sens, Guy de Noyers, founded the Saint-Pierre collegiate church in Saint-Julien-du-Sault. The chapter of eleven canons, which is attached to it, has, among other things, the charge of services at the Saint-Julien chapel of the Vauguillain castle. The church of the collegiate church left no trace. Around 1240, it is replaced by a Gothic church that will never be completed. Only the choir, buttresses and side gates were erected. The church was burned down and partially destroyed in the middle of the 14th century. The restoration began at the end of the 15th century, under the leadership of the Archbishop of Sens, Tristan de Salazar (1475-1519). Cardinal Louis de Bourbon, archbishop of Sens from 1535 to 1557, took charge of its completion by the complete reconstruction of the choir. He also tried to install stands. The nave, which was the responsibility of the parish, remained unfinished. We see it in the beautiful fasciculate pillars, designed to support the stone vault, which do not end (photo below). The vault will remain wooden. To the west, the nave is closed by a plank fence until 1735. As a result, the church of Saint-Pierre has no architectural unity. However, in 1840 it was added to the Historic Monuments Inventory for its stained glass windows of the 13th and 16th centuries, which constitute its true wealth and artistic interest.