William de Corbeil or William of Corbeil (c. 1070 – 21 November 1136) was a medieval Archbishop of Canterbury. Very little is known of William's early life or his family, except that he was born at Corbeil, south-east of Paris, and that he had two brothers. Educated as a theologian, he taught briefly before serving the bishops of Durham and London as a clerk and subsequently becoming an Augustinian canon. William was elected to the See of Canterbury as a compromise candidate in 1123, the first canon to become an English archbishop. He succeeded Ralph d'Escures who had employed him as a chaplain.
Throughout his archbishopric, William was embroiled in a dispute with Thurstan, the Archbishop of York, over the primacy of Canterbury. As a temporary solution, Pope Honorius II appointed William the papal legate for England, giving him powers superior to those of York. William concerned himself with the morals of the clergy, and presided over three legatine councils, which among other things condemned the purchase of benefices or priesthoods, and admonished the clergy to live a celibate life. He was also known as a builder; among his constructions is the keep of Rochester Castle. Towards the end of his life William was instrumental in the selection of Count Stephen of Boulogne as King of England, despite his oath to the dying King Henry I that he would support the succession of his daughter, the Empress Matilda. Although some chroniclers considered him a perjurer and a traitor for crowning Stephen, none doubted his piety.
William de Corbeil was most likely born at Corbeil on the Seine, possibly in about 1070. He was educated at Laon, where he studied under Anselm of Laon, the noted scholastic and teacher of theology. William taught for a time at Laon, but nothing else is known of his early life. All that is known of his parents or ancestry is that he had two brothers, Ranulf and Helgot; his brothers appear as witnesses on William's charters.
William joined the service of Ranulf Flambard, Bishop of Durham, as a clerk, and was present at the translation of the body of Saint Cuthbert in 1104. His name appears high in a list of those who were present at the event, implying that he may have held an important position in Flambard's household, but appended to his name is "subsequently archbishop", suggesting that his inclusion could have been a later interpolation. He was a teacher to Flambard's children, probably in about 1107 to 1109, but at some unknown date William appears to have transferred to the household of the Archbishop of Canterbury. Between 1107 and 1112 he went to Laon and attended lectures given by Anselm of Laon. By 1116 he was a clerk for Ralph d'Escures, Archbishop of Canterbury, with whom he travelled to Rome in 1117 when Ralph was in dispute with Thurstan, the Archbishop of York, over the primacy of Canterbury.
In 1118, William entered the Augustinian order at Holy Trinity Priory in Aldgate, a house of canons rather than monks. Subsequently, he became prior of the Augustinian priory at St Osyth in Essex, appointed by Richard de Beaumis, Bishop of London, in 1121.
After the death of Ralph d'Escures in October 1122, King Henry I allowed a free election, with the new primate to be chosen by the leading men of the realm, both ecclesiastical and secular. The monks of the cathedral chapter and the bishops of the kingdom disagreed on who should be appointed. The bishops insisted that it should be a clerk (i.e. a non-monastic member of the clergy), but Canterbury's monastic cathedral chapter preferred a monk, and insisted that they alone had the right to elect the archbishop. However, only two bishops in England or Normandy were monks (Ernulf, Bishop of Rochester, and Serlo, Bishop of Séez), and no monks other than Anselm of Canterbury, Ernulf, and Ralph d'Escures had been elected to an English or Norman see since 1091; recent precedent therefore favoured a clerk. King Henry sided with the bishops, and told the monks that they could elect their choice from a short list selected by the bishops. Perhaps unsurprisingly, the list contained no monks.
On 2 February or 4 February 1123, William was chosen from among four candidates to the See of Canterbury; the names of the three unsuccessful candidates are unknown. He appears to have been a compromise candidate, as he was at least a canon, if not the monk that the chapter had sought. William was the first Augustinian canon to become an archbishop in England, a striking break with the tradition that had favoured monks in the See of Canterbury. Although most contemporaries would not have considered there to be much of a distinction between monks and canons, William's election still occasioned some trepidation among the monks of the Canterbury chapter, who were "alarmed at the appointment, since he was a clerk".
William, like every other Canterbury archbishop since Lanfranc, maintained that Canterbury held primacy—in essence, overlordship—over all other dioceses in Great Britain, including the archbishopric of York. Thurstan had claimed independence, and refused to consecrate William when the latter demanded recognition of Canterbury's primacy; the ceremony was performed instead by William's own suffragan bishops on 18 February 1123. Previous popes had generally favoured York's side of the dispute, and the successive popes Paschal II, Gelasius II, and Calixtus II had issued rulings in the late 1110s and early 1120s siding with York. Calixtus had also consecrated Thurstan when both King Henry and William's predecessor had attempted to prevent Thurstan's consecration unless Thurstan submitted to Canterbury.
After travelling to Rome to receive his pallium, the symbol of his authority as an archbishop, William discovered that Thurstan had arrived before him, and had presented a case against William's election to Pope Callixtus II. There were four objections to William's election: first that he was elected in the king's court; second that the chapter of Canterbury had been coerced and was unwilling; third that his consecration was unlawful because it was not performed by Thurstan; and fourth that a monk should be elected to the See of Canterbury, which had been founded by Augustine of Canterbury, a monk. However, King Henry I and the Emperor Henry V, Henry I's son-in-law, persuaded the pope to overlook the irregularities of the election, with the proviso that William swore to obey "all things that the Pope imposed upon him". At the conclusion of the visit the pope denied the primacy of Canterbury over York, dismissing the Canterbury cathedral chapter's supposed papal documents as forgeries. The outcome was in accordance with most earlier papal rulings on the primacy issue, which involved not taking sides and thus reinforcing papal supremacy. William returned to England and was enthroned at Canterbury on 22 July 1123.
The archbishop's next opponent was the papal legate of the new Pope Honorius II, Cardinal John of Crema, who arrived in England in 1125. A compromise between York and Canterbury was negotiated, which involved Canterbury allowing York the supervision of the dioceses of Bangor, Chester, and St Asaph in return for Thurstan's verbal submission and the written submission of his successors. The pope, however, rejected the agreement, likely because he wished to preserve his own primacy, and substituted his own resolution. The papal solution was that Honorius would appoint William papal legate in England and Scotland, which was done in 1126, giving William the position over York, but it was dependent on the will of the pope, and would lapse on the pope's death. The arrangement merely postponed the problem however, as neither Thurstan nor William renounced their claims. That Christmas, at a royal court, Thurstan unsuccessfully attempted to claim the right to ceremonially crown the king as well as have his episcopal cross carried before him in Canterbury's province. As a result of his lengthy dispute with Thurstan, William travelled to Rome more frequently than any bishop before him except for Wilfrid in the 7th century.