The Cistercians invented the legal form of the modern religious order in the 12th century. Their reforms in the spiritual-liturgical and organizational-constitutional areas have permanently shaped high and late medieval monasticism. Through their return to self-sustenance, the inclusion of lay brothers, and a Europe-wide network with rulers, bishops, and local nobility, they left deep marks on society and the economy of their time, even outside the monastery. The book addresses the history of the Cistercians from their founding by Robert of Molesme and their greatest expansion under Bernard of Clairvaux to their religious, cultural, scientific, political, and socioeconomic significance, as well as the reforms and crises of modern times and the changed self-understanding in the present. Professor Dr. Jörg Oberste is a professor.