A type of small round window, called an oculus, had been used in Romanesque churches.
The facade of the Basilica of Saint Denis featured an early rose window on its west front.
This was made with plate tracery, where the design was formed by a group of variously shaped openings which appeared to be cut out of the wall.
A more ambitious model, with the armature of a wheel made of stone mullions, appeared at Senlis Cathedral in 1200.
A similar early Gothic window was constructed for the facade of Chartres Cathedral in 1215.
It was soon followed by the High Gothic window of the facade of Laon Cathedral (1200-1215).
In 1215, the two great transept windows of Chartres Chathedral were completed.
These became the model for many similar windows in France and beyond.
The amount of stained glass in Chartres was unprecedented; one hundred sixty four bays, with 2,600 square meters of stained glass.
A remarkably large amount of the original glass is still in place.

Not long after the introduction of the High Gothic rose window, Gothic architects, fearing that the interiors of the cathedrals were too dark, began experimenting with grisaille windows, which emphasized the important figures in the windows, and also brightened the interiors.
These were used at Poitiers Cathedral in 1270 and then by Chartres Cathedral around 1300.
Large bands of translucent gray glass were put around the fully colored figures of Christ, The Virgin Mary, and other prominent subjects.
A type of small round window, called an oculus, had been used in Romanesque churches. The facade of the Basilica of Saint Denis featured an early rose window on its west front. This was made with plate tracery, where the design was formed by a group of variously shaped openings which appeared to be cut out of the wall. A more ambitious model, with the armature of a wheel made of stone mullions, appeared at Senlis Cathedral in 1200. A similar early Gothic window was constructed for the facade of Chartres Cathedral in 1215. It was soon followed by the High Gothic window of the facade of Laon Cathedral (1200-1215). In 1215, the two great transept windows of Chartres Chathedral were completed. These became the model for many similar windows in France and beyond. The amount of stained glass in Chartres was unprecedented; one hundred sixty four bays, with 2,600 square meters of stained glass. A remarkably large amount of the original glass is still in place. 
Not long after the introduction of the High Gothic rose window, Gothic architects, fearing that the interiors of the cathedrals were too dark, began experimenting with grisaille windows, which emphasized the important figures in the windows, and also brightened the interiors. These were used at Poitiers Cathedral in 1270 and then by Chartres Cathedral around 1300. Large bands of translucent gray glass were put around the fully colored figures of Christ, The Virgin Mary, and other prominent subjects.
High Gothic