The Missa Caput was a musical setting of the Roman Catholic mass, dating from the 1440s, by an anonymous English composer. It circulated widely on the European continent in the mid-15th century and was one of the best-loved musical works of the early Renaissance in Europe, judging by the number of copies that have survived, and the number of imitations it inspired. It was influential both for its use of a tenor cantus firmus which unified all the movements and for being the first extended composition with a freely composed bass line, a feature with extraordinary ramifications in music history.[1] Among the many composers influenced by it are Guillaume Du Fay and Johannes Ockeghem.