The plan, defined by a tight rectangular shape with non-projecting transept, was determined by the church?s urban location. The three-bay choir is flanked by aisles extended into lateral chapels and terminated to the east by three shallow apsidal chapels. The six-bay aisled nave with double aisles and chapels is terminated by a western frontispiece with a Late Gothic tower to the north and a post-medieval tower, placed at an awkward angle, to the south.
The choir has a three-story elevation; the main arcade with inner and outer orders articulated with torus mouldings, sits atop cylindrical, drum-built columns. The middle level is a blind triforium in the form of a band of lancets, four per bay. The tall nave, on the other hand, has a two-story elevation. The sharp mouldings of the main arcade disappear into the streamlined piers; the clerestory very tall windows are closed in with a strip of masonry along the bottom performing the role of a triforium, The nave main vessel has elaborate lierne vaults
The town of Gisors, dominated by the castle, was on the front line between Capetians and Plantagenets.
Almost nothing is left of the old church, consecrated in 1119 in the presence of Pope Calixtus II. The new church, begun by Blanche de Castille in the second quarter of the 13th century, was consecrated in 1239 by Eudes Rigaud, archbishop of Rouen. This church survived until the fifteenth century, when a series of well-funded campaigns of construction extending to the 18th century, entirely transformed the western end of the church. The rich archive sources allow us to identify the masons engaged in the late Gothic work: Robert Jumel, Guillaume le Maistre, Pierre Gosse and Robert Grappin.
This work (Jumel and Le Maistre) began in the 1490s with the south transept and continued with choir chapels. From 1516 (Jumel) the south transept was under way, work completed by Robert Grappin who built the nave between 1520 and 1560 including the northern tower of the west façade (1536).
The oldest part of the church is the three-bay, three-story chevet with its flat east end (c 1220s-30s) pierced by an aperture opening into the fifteenth-century apse. Next comes the transept which retains the height of the choir. The fifteenth-century nave makes a complete break the old church?it is so tall that its upper parts butt up against the old crossing tower
The thirteenth-century chevet resembles the church of S-Sauveur of Les Andelys, while the late Gothic extension is linked with Magny-en-Vexin, a work also associated with Robert Jumel. The nave, on the other hand, recalls the chevet of Saint-Etienne de Beauvais, a work begun around 1502 by Martin Chambiges. Spiral forms of the nave aisle intermediary piers like those of the ambulatory of S-Séverin, Paris.
Bottineau-Fuchs, Y., Haute-Normandie gothique, Paris, 2001, 215-221.
Catholic Church, L'Office des Saints Gervais et Protais, martyrs, patrons de Gisors, Gisors, 1835
Cheron, P.; Hérold, M.; Leroy, T., Gisors: église paroissiale Saint-Gervais Saint-Protais: les verrières, Rouen, 1993
Dubreuil, G., *Essai historique sur Gisors