Cistercians significant person Bernard of Clairvaux
High and Late Middle Ages
Spread: 1111–52
By 1111 the ranks had grown sufficiently at Cîteaux, and Stephen sent a group of 12 monks to start a "daughter house", a new community dedicated to the same ideals of the strict observance of Saint Benedict. The Cistercians were officially formed in 1112. The "daughter house" was built in Chalon sur Saône in La Ferté on 13 May 1113.In the year of 1112, a charismatic young Burgundinian nobleman named Bernard arrived at Cîteaux with 35 of his relatives and friends to join the monastery. A supremely eloquent, strong-willed mystic, Bernard was to become the most admired churchman of his age. In 1115, Count Hugh of Champagne gave a tract of wild, afforested land known as a refuge for robbers, forty miles east of Troyes, to the order. Bernard led twelve other monks to found the Abbey of Clairvaux, and began clearing the ground and building a church and dwelling.  The abbey soon attracted zealous young men.  At this point, Cîteaux had four daughter houses: Pontigny, Morimond, La Ferté and Clairvaux.
After Saint Bernard's entry, the Cistercian order began a notable epoch of international expansion. As his fame grew, the Cistercian movement grew with it.In 1129 Margrave Leopold the Strong of Styria called upon the Cistercians to develop his recently acquired March which bordered Austria on the south.  He granted  monks from the Ebrach Abbey in Bavaria an area of land just north of what is today the provincial capital Graz, where they founded Rein Abbey.  At the time, it was the 38th Cistercian monastery founded but, due to the dissolution down the centuries of the earlier 37 abbeys, it is today the oldest surviving Cistercian house in the world.
Thirteen Cistercian monasteries, all in remote locations, were founded in Wales between 1131 and 1226. The first of these was Tintern Abbey, which was sited in a remote river valley, and depended largely on its agricultural and pastoral activities for survival.  Other abbeys, such as at Neath, Strata Florida, Conwy and Valle Crucis became among the most hallowed names in the history of religion in medieval Wales. Their austere discipline seemed to echo the ideals of the Celtic saints, and the emphasis on pastoral farming fit well into the Welsh stock-rearing economy.
In Yorkshire, Rievaulx Abbey was founded from Clairvaux in 1131, on a small, isolated property donated by Walter Espec, with the support of Thurstan, Archbishop of York. By 1143, three hundred monks had entered Rievaulx, including the famous St Ælred. It was from Rievaulx that a foundation was made at  Melrose, which became the earliest Cistercian monastery in Scotland. Located in Roxburghshire, it was built in 1136 by King David I of Scotland, and completed in less than ten years. Another important offshoot of Rievaulx was Revesby Abbey in Lincolnshire.Fountains Abbey was founded in 1132 by discontented Benedictine monks from St. Mary's Abbey, York, who desired a return to the austere Rule of St Benedict. After many struggles and great hardships, St Bernard agreed to send a monk from Clairvaux to instruct them, and in the end they prospered. Already by  1152, Fountains had many offshoots, including  Newminster Abbey (1137) and Meaux Abbey (1151).In the spring of 1140, Saint Malachy, Archbishop of Armagh, visited Clairvaux, becoming a personal friend of Abbot Bernard and an admirer of Cistercian life. He left four of his companions to be trained as Cistercians, and returned to Ireland to introduce Cistercian monasticism there. Mellifont Abbey was founded in County Louth in 1142 and from it daughter houses of Bective Abbey in County Meath (1147), Inislounaght Abbey in County Tipperary (1147–1148), Baltinglass in County Wicklow (1148), Monasteranenagh in County Limerick (1148), Kilbeggan in County Westmeath (1150) and Boyle Abbey  in County Roscommon (1161). Malachy's intensive pastoral activity was highly successful: "Barbarous laws disappeared, Roman laws were introduced: everywhere ecclesiastical customs were received and the contrary rejected... In short all things were so changed that the word of the Lord may be applied to this people: Which before was not my people, now is my people."
Meanwhile, the Cistercian influence more than kept pace with the material expansion. St. Bernard had become mentor to popes and kings, and in 1145, King Louis VII's brother, Henry of France, entered Clairvaux.  That same year, Bernard saw one of his monks elected pope as Pope Eugene III.  Eugene was an Italian of humble background, who had first been drawn to monasticism at Clairvaux by the magnetism of Bernard. At the time of his election, he was Abbot of Saints Vincenzo and Anastasio outside Rome.A considerable reinforcement to the Order was the merger of the Savigniac houses with the Cistercians, at the insistence of Eugene III. Thirteen English abbeys, of which the most famous were Furness Abbey and Jervaulx Abbey, thus adopted the Cistercian formula. In Dublin, the two Savigniac houses of Erenagh and St Mary's became Cistercian. It was in the latter case that medieval Dublin acquired a Cistercian monastery in the very unusual suburban location of Oxmantown, with its own private harbour called The Pill.By 1152, there were 54 Cistercian monasteries in England, few of which had been founded directly from the Continent. Overall, there were 333 Cistercian abbeys in Europe, so many that a halt was put to this expansion.  Nearly half of these houses had been founded, directly or indirectly, from Clairvaux, so great was St Bernard's influence and prestige. He later came popularly to be regarded as the founder of the Cistercians, who have often been called Bernardines. Bernard died in 1153, one month after his pupil Eugene III.Theology
By far the most influential of the early Cistercians was Bernard of Clairvaux. According to the historian Piers Paul Read, his vocation to the order, by deciding "to choose the narrowest gate and steepest path to the Kingdom of Heaven at Citeaux demonstrates the purity of his vocation".  His piety and asceticism "qualified him to act as the conscience of Christendom, constantly chastising the rich and powerful and championing the pure and weak."  He rebuked the moderate and conciliatory Abbot Peter the Venerable for the pleasant life of the Benedictine monks of Cluny.  Besides his piety, Bernard was an outstanding intellectual, which he demonstrated in his sermons on Grace, Free will and the Song of Songs.  He perceived the attraction of evil not simply as lying in the obvious lure of wealth and worldly power, but in the "subtler and ultimately more pernicious attraction of false ideas".  He was quick to recognise heretical ideas, and in 1141 and 1145 respectively, he accused the celebrated scholastic theologian Peter Abelard and the popular preacher Henry of Lausanne of heresy.  He was also charged with the task of promulgating Pope Eugene's bull, Quantum praedecessores, and his eloquence in preaching the Second Crusade had the desired effect: when he finished his sermon, so many men were ready to take the Cross that Bernard had to cut his habit into strips of cloth.Although Bernard's De laude novae militiae was in favour of the Knights Templar, a Cistercian was also one of the few scholars of the Middle Ages to question the existence of the military orders during the Crusades.  The English Cistercian Abbot Isaac of l'Etoile, near Poitiers, preached against the "new monstrosity" of the nova militia in the mid-12th century and denounced the use of force to convert members of Islam.  He also rejected the notion that crusaders could be regarded as martyrs if they died while despoiling non-Christians. Nevertheless, the Bernardine concept of Catholic warrior asceticism predominated in Christendom and exerted multiple influences culturally and otherwise, notably forming the metaphysical background of the otherworldly, pure-hearted Arthurian knight Sir Galahad, Cistercian spirituality permeating and underlying the medieval "anti-romance" and climactic sublimation of the Grail Quest, the Queste del Saint Graal—indeed, direct Cistercian authorship of the work is academically considered highly probable. Cistercian-Bernardine chivalrous mysticism is especially exhibited in how the celibate, sacred warrior Galahad, due to interior purity of the heart (cardiognosis in Desert Father terminology), is alone in being granted the beatific vision of the eucharistic Holy Grail.