The construction of the abbey church of St Denis in Paris, the first Gothic Cathedral was begun in around 1140. Combining stained glass windows, flying buttresses, choir vaulting and rib vaults, it was a daring innovation in architecture. The specifications were set by the abbot of St Denis, Suger.
Under the direction of the new Bishop of Paris, Maurice de Sulley, a new church was planned for Notre Dame Cathedral in Paris. The major construction work would last until around 1235 while minor construction would continue for another 100 years after that. The existing church was pulled down and construction work began in 1163.
Bishop Maurice de Sulley united the two Cathedrals of Paris, St. Stephen's and the Blessed Virgin with the construction of Notre Dame Cathedral and laid the foundations of the new building that was designed by Eudes de Montreuil.