The Cistercians (White Monks) were the most successful monastic experiment to emerge from the tumultuous intellectual and religious fervour of the eleventh and twelfth centuries. By around 1150 they had established houses the length and breadth of Western Christendom and were internationally renowned. They sought to return to a simple form of monastic life, as set down in the Rule of St Benedict, and preferred rural locations "far from the haunts of men." But, as recent research has shown, they were by no means isolated from society but influenced, and were influenced by, the world around...