The cathedral suffered badly from the excesses of the French Revolution, becoming successively a "Temple de la Raison", then a stable, then a warehouse.

The Concordat of 1801 was an agreement between Napoleon and Pope Pius VII, signed on 15 July 1801 in Paris, which sought national reconciliation between revolutionaries and Catholics.

[1] The building is notable for its eclectic mix of styles and idiosyncrasies, such as the incomplete north tower on the main west-facing entrance.

The seat of the ancient bishopric of Dol, the Saint-Samson cathedral dates to the 13th century and is primarily Gothic in style with both Norman and English influences.

This old church was replaced by a Romanesque style cathedral which was in turn destroyed in 1203 by the soldiers of Jean sans Terre and little is left of that building today.

He died in 565 in Dol having nominated Magloire as his successor and his tomb was to become the destination of numerous pilgrims and is included in the Breton Tro Breizh.

[2] In 1203, the English king, John Lackland, known in France as "Jean sans Terre" and the presumed murderer of Arthur de Bretagne burned the Romanesque cathedral down and occupied Dol for one year; there are few remnants of that building.

Then, fearing for his soul and in a fit of remorse, he put up funds towards the cathedral's reconstruction which was started the same year under the episcopacy of the bishop Jean VII de Lizaunet.

In a small corner of the south tower, there is a carving depicting "Jean sans Terre" bearing a rictus grin.

Stendhal described the cathedral as "un des ouvrages les plus remarquables que l'architecture gothique puisse offrir à notre admiration".

The central arcade shows scenes from the life of Christ: The Calvary; Jesus healing a sick man; Jesus amongst the lawyers; the agony in the garden of Gethsemane; Mater Dolorosa (Our Lady of Sorrows); Simon of Cyrene; the Adoring Angels; the "Sainte-Face" (the face of Christ) and Adam and Eve (A copy of the bas-relief at Notre-Dame de Paris) The east facing arcade by the well shows scenes from the life of the Virgin Mary: Mary carrying the baby Jesus; the flight into Egypt; the coronation; the Visitation; the Annunciation; the Nativity and the Annunciation to the shepherds.

Etienne Nicol described Boucher's carvings "Dignes de la grande tradition des imagiers en granite du moyen age".

The inscription reads "IOANIS - IAMEZ - IURIU - LAUTI - LEHONII - COMENDAT - DOL - THESAU - ET - CANO - IMPESA - ET - CURA - STRUCTUM - AC - ORNATU - SEPULCRU - M - VCC - VII.

The cathedral statuary includes a fine 14th-century wooden statue of the Virgin Mary carrying Jesus which has been polychromed and gilded.

[2] In the chapel dedicated to saint-Gilles and saint-Roch is a 1901 altar with a relief depicting Saint Thuriau blessing a barbarian, this executed by the sculptor Augerie.

The altar altarpiece and statues are by Jean-Marie Valentin and date to 1873 and the chapel's oil paintings are the work of the Rennes artist Lemoine.

The stained glass tells us something of Saint Gilduin; his refusal of the bishopric, his illness, his transfer to Notre-Dame in Chartres and his death.

The chapel altar is carved from wood and includes a tabernacle and two bas-reliefs, one depicting the "Annunciation" and the other the "Couronnement de la Vierge".

The chapel is dedicated to Saint Samson and dates to the first half of the 14th century, being built during the episcopacy of Jean du Bosc (1312–24).

Even was the 20th bishop of Dol and in the scene beneath his image, the deacon Gilduin is shown refusing the bishopric and recommending to the Pope that Even is given the post.

Leucher was the 4th bishop of Dol and in the scene beneath his image we see Leichet using the cross of Saint Samson to put out a fire which threatened the church.

The lancets hold the images of the three saints and the tympanum depicts the Virgin Mary being blessed by Jesus and a group of angels and cherubs.

This chapel contains a monument, installed in 1920, dedicated to those men of Dol who lost their lives in the 1914-1918 war and sculpted by André César Vermare.

In this chapel, there is a mosaic altar dedicated to Notre-Dame de Pitié executed in 1902 and the work of the sculptor Augerie and the mosaicist Isidore Odorico.

During the 1944 bombing which preceded Dol-de-Bretagne's liberation from German occupation, explosions badly damaged the window necessitating restoration work by the master glazier Jacques Gruber.

In the window's upper level we see Magloire enjoying the solitude of Mont-Dol, curing a rich Breton who gave him half of the island of Sercq where he built a monastery and rescuing a fisherman drowning in the sea.

[2] The same atelier of Jacquier and Küchelbecker installed the window depicting scenes from the life of Saint Anne in the north transept.

His death resulted from a conspiracy involving Pascweten, Wrhwant, and Wigo, son of Riwallon, Count of Cornouaille, but they quickly fell out with each other and a civil war followed until 876.

[37] When the Normans invaded Brittany in 878 it was decided to move Samson's remains to a safer place but the sarcophagus had been too heavy to transport and was left in Dol.

High up in the eastern side of the south transept there is a window dating to around 1265 to 1270 depicting two other Dol bishops, Thibaud de Pouancé and Henri Du Bois.