Hildebert (c. 1055 – 18 December 1133) was a French ecclesiastic, hagiographer and theologian. From 1096/7, he was bishop of Le Mans, then from 1125 until his death archbishop of Tours. Sometimes called Hildebert of Lavardin, his name may also be spelled Hydalbert, Gildebert, or Aldebert.
Hildebert was born of poor parents at Lavardin, near Vendôme, and was intended for the church. He was probably a pupil of Berengar of Tours, and became master (scholasticus) of the school at Le Mans; in 1091 he was made archdeacon and in 1096 or 1097 bishop of Le Mans. He had to face the hostility of a section of his clergy and also of the English king, William II, who captured Le Mans and carried the bishop with him to England for about a year.
Hildebert then (in 1100 or 1103) travelled to Rome and sought permission to resign his bishopric, which Pope Paschal II refused. In 1116 his diocese was thrown into great confusion owing to the preaching of Henry of Lausanne, who was denouncing the higher clergy, especially the bishop. Hildebert compelled him to leave the neighborhood of Le Mans, but the effects of his preaching remained.
In 1125 Hildebert was translated unwillingly to the archbishopric of Tours, where he came into conflict with the French king Louis VI about the rights of ecclesiastical patronage, and with the bishop of Dol about the authority of his see in Brittany. He presided over the Synod of Nantes, and died at Tours probably on December 18, 1133. Hildebert built part of the cathedral at Le Mans. Some writers have referred to him with the title of saint, but there appears to be no authority for this. He was not a man of very strict life; his contemporaries, however, had a very high opinion of him and he was called egregius versificator by Orderic Vitalis.