THIBAUT (or Theobald) IV. (1201-1253), count of Champagne and Brie, and king of Navarre, French poet, was born at Troyes in 1201. His father, Thibaut III. of Champagne, died before his son's birth, and his mother, Blanche of Navarre, was compelled to resign the guardianship of the young prince to Philip Augustus, king of France, but there is little doubt that the child was acquainted with Chrétien de Troyes and the other trouvères who found patronage at the court of Champagne. Thibaut's verses belong to what is called “courteous” poetry, but they have a personal note that distinguishes them from mere exercises. They are addressed to Blanche of Castille, the wife of Louis VIII., and Thibaut's relations with her have been the subject of much controversy. The count took part with Louis in the crusade against the Albigenses, but in 1226, with no apparent reason, left the king and returned to Champagne. Three months later Louis died under doubtful circumstances, and Thibaut was accused by his enemies of poisoning him to facilitate his own intrigue with Blanche. The real reason for Thibaut's desertion appears to have been a desire to consolidate his position as heir-apparent of Navarre by an alliance with the disaffected nobility of the south of France, but from this confederation Blanche was skilful enough to detach him. The resentment of the league involved him in a war in which Champagne was laid waste, and his capital saved only by the royal intervention. In 1234 he succeeded his uncle, Sancho VII., as king of Navarre, and from this period date his most fervent songs in praise of his lady. The crusade turned Thibaut's thoughts to religion, and he announced his intention of singing henceforth only in honour of the Virgin. Unfortunately his devotion took darker forms, for before sailing for the Holy Land he ordered and witnessed the burning of a hundred and eighty-three unfortunate men and women convicted of Manichaeism. The years 1239 and 1240 were spent in Palestine, and from the time of his return Thibaut devoted himself to efforts for the improvement of his dominions that won for him the title of le Bon. He died at Pampeluna on the 14th of July 1253.

Thibaut was the most popular of all the 13th century songwriters, and his work is marked by a grace and sweetness which he owes perhaps in part to his association with the troubadours of the south. He is said to have set his own songs to music. It seems doubtful whether the notes that have come down to us can with justice be attributed to him, but there is no contesting the musical quality of his verse. His fame spread beyond the Alps, and Dante admired his poetry. He was one of the most celebrated authors of jeux-partis, elaborate discussions between two interlocutors, usually on the subject of love.

His works were edited in 1851 by P. Tarbé in his Chansonniers de Champagne.