Originally, Bernard de Clairvaux, a personality who was influent on the medieval Christian West

« But the more he becomes weak and languishing by the infirmities of his body, the more vigorous and stronger he becomes by the grace which animates his spirit, never stopping to make things deserving of memory, and always crowning his actions which are very important by others even bigger, which all the more deserve to be public and known by being written, as he keeps them secret and hidden by keeping them silent. »
That is the way Guillaume of Saint Thierry said his farewells to Bernard of Clairvaux in the First Life of S. Bernard that he wrote in the second half of the XIIth century.

Bernard de Clairvaux (1090-1153) is certainly the most famous character from the order of Cîteaux, to which he gave all its importance. He came from the Burgundian aristocracy and he was one of the most important men of the XIIth century. First abbot of the monastery of Clairvaux, Bernard was a fertile writer. He left us a rich work composed of several treaties, collections of sermons and a highly enriched correspondence.

Saint Bernard had a double effect. His impulse of foundation allowed Clairvaux to spread out quickly. At the end of the XIIth century, the abbey counted not less than 170 daugther abbeys. Those abbeys were established by monks who came from Clairvaux but also independent abbeys which chose to put themselves under the influence of Clairvaux.

He was also involved in all the big ecclesiastical affairs of his time, as the regulation of papal elections, the protection of orthodoxy, the preaching of the second crusade, the political interventions and diplomatic missions. Beyond the monasticism, Saint Bernard wanted to contribute to the reform of the whole Christendom.

His mystical theology, which was elaborated in the melting pot of the monasticism, deeply influenced all the Christian thought. The library of the abbey is thus just like his founder, the most influential personality of the XIIth century.
He was canonized in 1174.