The remarkable growth of Cluny Abbey in the Middle Ages is linked to various factors. It is due first to the general exemption granted to the Cluniacs, whose monks and nuns depended directly on the pope. On the other hand, from the beginning, the abbots in post received the mission to reform a certain number of houses that Cluny often assimilated. Finally, the exceptional abbots who succeeded one another at its head, by their authority and political ties, significantly increased the temporality of the abbey and extended the branches of its network to Europe and even to the Holy Land.