William of St-Thierry was a twelfth-century theologian and mystic born in Liège. After entering the monastery of St. Nicaise in Reims, he eventually served as the abbot of Saint-Thierry. He maintained a close, lifelong friendship with Bernard of Clairvaux, who encouraged his leadership despite William's personal desire to join the Cistercian Order earlier. Later in life, following periods of illness, he joined the Cistercians at Signy-l'Abbaye. He is recognized as a blessed figure in the Catholic tradition for his profound spiritual insights and theological contributions.