Hincmar, a celebrated churchman of the 9th century, of the family of the Counts of Toulouse, was born in 806. He was educated in the monastery of St Denis; was named abbot of the abbey of Compiègne and St Germain; and in 845 was elected Archbishop of Rheims. Rothadins, Bishop of Soissons, and suffragan of Hincmar, deposed a priest of his diocese, who appealed to Hincmar, as metropolitan, and was ordered by him to be restored to office. Rothadins, resisting this order, and having been in consequence excommunicated by the archbishop, appealed to the pope, Nicholas I., in 862, who at once ordered Hincmar to restore Rothadins, or to appear at Rome to vindicate the sentence. Ultimately Nicholas annulled the sentence. Hincmar, after some demur, was forced to acquiesce, and Rothadins was restored to his see. Hincmar wrote much against the strong predestinarian views of the monk Gottschalk, whom he united with others in degrading and imprisoning. Gottschalk died in prison after eighteen years' confinement.
The conduct of Hincmar is also historically interesting in relation to the temporal power of the medieval papacy. Under Adrian II. a question arose as to the succession to the sovereignty of Lorraine on the death of King Lothaire, the pope favouring the pretensions of the Emperor Lewis in opposition to those of Charles the Bold of France. To the mandate which Adrian addressed to the subjects of Charles and to the nobles of Lorraine, accompanied by a menace of the censures of the church, Hincmar offered a firm and persistent opposition. He was equally firm in resisting the undue extension of the royal prerogative in ecclesiastical affairs. When the Emperor Lewis III. sought to obtrude an unworthy favourite upon the see of Beauvais, Hincmar boldly demonstrated, and fearlessly denounced the unjustifiable usurpation. Hincmar died in the year 882.
His works were collected by the Jesuit Sirmond (1645), and are to be found in Migne's Cursus Patr. Compl. His Annales Bertiniani, from 861 to 882, are in vol. i. of Pertz's Monumenta. See Prichard, Life and Times of Hincmar (1849), and German works by Norden (1862), Sdrøle (1881), and Schrørs (1884).