Saint Bernard of Clairvaux (1090-1153) chose the monastic life at the age of 22. In 1115, after three years at Citeaux, Bernard was sent to Clairvaux to found the abbey, where he remained father-abbot until his death. Far from remaining cloistered, he travelled the roads of Europe. He kept up an abundant correspondence with princes, brother monks and, in particular, Hildegard of Bingen. He was an important promoter of the Cistercian order. By the time of his death in 1153, 343 Cistercian abbeys had sprung up across Europe.
He was canonised in 1154 and proclaimed a Doctor of the Church in 1830 by Pope Pius VIII.