The Roman province around Saintes, a rich land of crop and woods, was christianized very early. In the 11th and 12th centuries, the Saintonge was covered with parish churches. The Romanesque art left in our region a very beautiful testimony of its architecture then Gothic art appeared and many buildings like the church of Champagne present today a mixed architecture. These projects were often organized by abbots from the monasteries. Creators and artists, through the parish churches, they widely disseminated the Christian vision of man and the universe. Located on a road leading to the sea, Champagne was in the bishopric of Saintes.
On the Saint André church, several construction campaigns were carried out from West to East at very close intervals. This architecture shows a lot of hesitation in the construction choices. The first two bays of the nave and the eastern façade were built in the 12th century. It is therefore a single nave building that had to be intersected by a transept but only the south arm was built. It now bears a three-storey bell tower, the second level of which has the peculiarity of having a blind arcade and rounded corners. At the beginning of the Gothic period, a vast apse was erected in the prolongation of the Romanesque nave: a long straight span vaulted with quadripartite ogives and an apse with an eastern wall slightly rounded and vaulted with ogives. At the same time there was placed on the south arm of the transept an apse with five panels, also vaulted with ogives, but on consoles. In the 16th century, a rectangular chapel was established on this apse.
The western façade shows in height a large bay with two arches decorated with fleurons and stems , typical in Saintonge in the middle of the 12th century. It is framed by two small arcades. The columns which receive the different bows carry capitals with rings. Note also a row of modillions adorned with heads and monsters. On the north door there are three vaults, decorated with florets like those of the western bay, beautiful half palmettes alternately erect and reversed, and palmettes inscribed in foliage. At the extremities, there is the presence, on one side, of a "woman with snakes" and a dragon with a coiled tail, and, on the other, a basil, a legendary monster. In the nave, one will notice, a large bearded head and a woman holding records marked with the sign of the cross, no doubt Eucharistic loaves. Other capitals are lined with foliage.