Stained glass windows of Chartres Cathedral

However, most of the windows were probably made between 1205 and 1240 for the present church, taking in the Fourth Crusade (bringing a large number of important relics to Chartres[4]) and the Albigensian Crusade, as well as the reigns of Philip II Augustus (1180–1223) and Louis VIII (1223–1226), with the building's consecration finally occurring in 1260 under Louis IX (1226–1270).

The destruction of Reims Cathedral and its stained glass in 1914 caused shock across France and led to all Chartres' windows being taken out and stored throughout both world wars.

[5] Since the late 10th century all churches across Europe had been built in a common Romanesque style, with thick walls supported by massive external buttresses and often with barrel vaulted naves.

This limited the number of windows, leading to a play of light and shade which builders compensated for by adding internal frescoes in bright colours.

Genesis 1.1-5 evoked darkness and light, as elaborated by Abbot Suger alongside his reasons for rebuilding the choir of the church at Saint-Denis Abbey.

[6] This new art (known at the time as Opus Francigenum and only named Gothic architecture in the 17th century) spread from the Kingdom of France right across Europe.

To quote Louis Grodecki, it was in the Abbey Church of St Denis "that Gothic architecture first emerges as a consistent way of building, fruitful in its solutions of independent ogives, arcus singulariter voluti as the abbot called them.

In around 827 Louis the Pious had given St Denis Abbey a Greek manuscript of the works of Pseudo-Dionysius the Areopagite, which he had himself received from Michael II, Emperor of Byzantium.

This manuscript and John Scotus Eriugena's interpretation of it was the origin for the whole mystical Free Spirit current in medieval theology, which strongly influenced Suger, an exact contemporary of Hugues de Saint-Victor, the most notable master in Paris at the time.

Entering by the cathedral's west door and moving towards the choir and high altar to receive communion, the faithful had to be able to go through the different stages described by Hugues de Saint-Victor.

Using the language of colour and changing harmonies according to the time of day, the stained glass windows formed a doxological liturgy, a canticle whose words were the images, a metaphor first used by Pope Honorius III in his 1219 letter to Stephen Langton - "That the happy church at Canterbury may thus sing a new song to the Lord".

Stained glass windows were also linked with theological questions about baptism and the eucharist, two sacraments violently affected by heresies but firmly doctrinally defended by Eudes de Sully and the Fourth Lateran Council.

Augustine of Hippo's City of God had already written that heretics would escape eternal damnation if they had received baptism and communion.

At a time when the kings of France were defending their hereditary right to rule, Chartres' windows of the Tree of Jesse showed the continuous line from the Kings of Judah to Christ via the Virgin Mary, whilst the windows on the life of Thomas Becket showed the recent clash in England between temporal and spiritual power.

The windows on the life of St Sylvester were placed symmetrically with those on the life of Charlemagne - the former show Constantine as a bloodthirsty tyrant who later summoned St Sylvester to hear his repentance and heal him of leprosy, hearing his preaching and submitting to him after baptism, whilst those of Charlemagne show a royal figure that the Church could support (indeed, one that had been canonised on 29 December 1165 by Antipope Paschal III, though that canonisation was not recognised by the mainstream Church).

As taken up in the design of other Gothic churches, Suger's arguments showed how all four senses of scripture were present: The windows can be grouped in several different ways.

Another interpretation divides the windows by their location in the nave, transepts and choir, with each of the three linked to a period in the history of revelation.

The monk Theophilus Presbyter described glass-production in minute detail early in the 12th century in his treatise Schedula diversum artium - the glass-painter was to trace the composition of a window on a panel of bleached wood, before cutting the glass sections on it and finally painting and assembling them.

[13] The bays' numbers were set in the Corpus vitrearum, running from 0 to 99 on the lower level, starting at the chevet and going as far as the nave facade.

This consists of three lancets (bays 49–51) below a large rose-window (141), the latter formed of a 12-lobe eye and 12 sections each made up of 2 medallions, along with twelve smaller circles separated by quatrefoils.

It post-dates Suger's Stirps Jessein the stained glass of the chevet of Saint-Denis, named after the first words of the responsorial hymn by Fulbert of Chartres for the Feast of the Virgin Mary[Note 3]., but the latter has been heavily restored.

It is made up of five lancets below a large rose window formed of a twelve-lobe eye, then twelve sections made up of medallions, then twelve circles, then twelve quatrefoils and finally twelve semi-circles bearing medallions The central lancet shows the Madonna holding the Christ Child in her arms, flanked symmetrically by the four evangelists (left to right Luke, Matthew, John and Mark) sitting on the shoulders of the major Old Testament prophets (left to right Jeremiah, Isaiah, Ezekiel and Daniel), recalling a famous image by Bernard of Chartres, master and chancellor of the School of Chartres, handed down by John of Salisbury in colophon 400 of his Metalogicon - "Bernard of Chartres said that we are like dwarves perched on the shoulders of giants, and we can see better and further than them not because our sight is more piercing or our size is larger, but because we are raised into the air and carried up into the air thanks to their gigantic height".

[Note 4] Below the Virgin Mary are figures of Pierre of Dreux or Pierre Mauclerc and Alix of Thouars, along with the coats of arms of the counts of Dreux on the left (to the left below Jeremiah) and representations their daughter Yolande of Brittany (below Ezekiel) and their eldest son Jean le Roux (born in 1217).

At the window's centre is Christ in Majesty, whilst running clockwise from bottom left the first circle shows the four living creatures of a lion, a bull, a man and an eagle, also seen as symbols of the Four Evangelists.

[16][17] "Notre-Dame de la Belle-Verrière", one of 75 representations of the Virgin Mary in Chartres Cathedral, owes its fame to this exceptional cobalt blue.

It was in this chapel that Pope Innocent III launched the Albigensian Crusade in 1208, mentioning the mission of the apostles and underlining that bishops were their successors.

Its construction involved all parts of medieval society – sovereigns (whose arms are seen in the north transept facade windows), nobles from the Chartres, Île-de-France and Normandy regions, the cathedral chapter and the trade guilds.

Nearly thirty confraternities and corporations also funded windows and are also shown, including those for carpenters, labourers, wine growers, masons, stone cutters, drapers, furriers and bakers.