Were Europe's great cathedrals built by Pagan hands?

While there may have been pagans who worked on many of the Cathedrals of Europe I doubt we can say Europe's great catherdrals were built by pagans. Most of those involved were very aware that they were building these structures for the glory of God. Many required generations of skilled craftsmen so that the work was ped down from father to son for more than a hundred years. Probably many felt they could buy their way into Heaven with their toil. I'm sure that was preached to them from the foolish leaders of the church, those who also believed that one could buy indulgences to guarantee a place in Heaven.