In 1100 AD, Laon was a very rich town in northern France, with strong walls and a lot of farmland. It’s on top of a high hill, so Laon (pronounced LON but you can just barely hear the N) was pretty much safe from enemies. The king of France had put Laon under the rule of a bishop, Bishop Gaudry, but the people of Laon wanted to be independent and rule themselves. In 1112 the people of Laon revolted, killed Bishop Gaudry and some of his friends, and burned down the bishop’s palace and (perhaps accidentally) also the cathedral.
So Laon needed a new cathedral. It took a while to get around to it, but finally in 1160 the Christian people of Laon began building the choir (the apse) of the new church. A hundred years had gone by since Matilda built the Abbaye aux Dames in Caen, and people were richer, so the architect at Laon was able to build a bigger and more impressive church. At Laon, the roof was 78 feet high.
Laon was one of the first cathedrals built in the new Gothic style, with pointed arches showing you the way up to Heaven. Like the Abbaye aux Dames, Laon had a flat end in the apse, and a six-part groin vault for the stone roof. The roof was a little higher than at the Abbaye aux Dames, held up by big stone buttresses leaning against the outside walls.
The fighting between the people and the bishop continued for the next hundred years, with the king taking first one side and then the other, until 1239, when the people of Laon won their freedom.