He served as canon of Soissons and Paris but soon retired to the solitude of Grandmont Abbey until dissension arose between the fathers and lay brothers. He then joined the Cistercians who were well known for their sanctity and austerity.

After some time in that order, William served as abbot of Fontaine-Jean and later Chalis. In 1200, he was elected Archbishop of the Church of Bourges, but it was only after receiving orders from the Pope and the Abbot of Citeaux that he agreed to leave his beloved solitude to accept this assignment.

As Archbishop, he redoubled his austerities so that he might do penance for others as well as for himself. He believed he had been sent chiefly to serve his flock and assisted them both spiritually and corporally. He dealt gently with penitent sinners but was inflexible towards the impenitent. William always wore a hair-shirt under his habit and never ate meat. With humility and patience he overcame opposition from his chapter and other clergy and converted many Albigensian heretics.

As he was preparing for a mission to Albigenses, he became very ill, and at his request, was laid in his hair-shirt upon ashes and died just past midnight on the morning of January 10, 1209. His body was interred in his cathedral, and after being honored by many miracles, it was enshrined in 1217. He was canonized by Pope Honorius III the next year. He is the patron saint of our parish and of adopted children.