Which Catholic saint is associated with the medieval hymn sequence Dies Irae?

Thomas of Celano is traditionally associated with the medieval hymn sequence Dies Irae.

Thomas was an Italian friar who joined the newly founded Franciscan movement during the lifetime of Francis of Assisi. He became one of the earliest biographers of Francis and wrote the Vita prima and Vita secunda, important sources for the saint’s early biography.

The Dies Irae, whose title means “Day of Wrath,” is a Latin sequence describing the Last Judgment. It was used for centuries in the traditional Roman Catholic Requiem Mass and became one of the best-known texts of medieval sacred poetry.

Older Catholic and scholarly traditions commonly attribute the poem to Thomas of Celano, although authorship has been debated. Jacopone da Todi is sometimes proposed as an alternative, which is why the attribution should be described as traditional rather than absolutely certain. Thomas died around 1260 and was later honored as a blessed or saint in Franciscan tradition.