It was Abbot Suger (1081-1151) who brought light into the Saint-Denis Basilica. The glass painters invented the “Saint-Denis blue” or “Suger blue”, which was copied in the cathedrals of Chartres and Le Mans. In the 12th century, Suger had a newly designed luminous chevet built “in three years, three months and three days”, which was later called Gothic. A master glassmaker was even employed full time to clean the stained glass windows, something never seen before. Around the ambulatory, each of the seven chapels is lit by two stained glass windows. At the end of the 13th century, the Gothic style spread throughout Europe.