Bernard of Clairvaux; O.Cist (1090 - August 20; 1153) was a French abbot and the primary builder of the reforming Cistercian order.

After the death of his mother; Bernard sought admission into the Cistercian order. Three years later; he was sent to found a new abbey at an isolated clearing in a glen known as the Val d'Absinthe; about 15 km southeast of Bar-sur-Aube. According to tradition; Bernard founded the monastery on 25 June 1115; naming it Claire Vall閑; which evolved into Clairvaux. There Bernard would preach an immediate faith; in which the intercessor was the Virgin Mary.

In the year 1128; Bernard assisted at the Council of Troyes; at which he traced the outlines of the Rule of the Knights Templar; who soon became the ideal of Christian nobility.