Since the late twelfth century, the Cathedral of Santiago in Compostela has possessed a manuscript entitled Jacobus (or Codex Calixtinus). How it found its way to Compostela is not known for certain, but it is undoubtedly a French product, probably compiled or written in Cluny around 1150.

Although they represent a mere ten percent of the music in Jacobus, the polyphonic works have received attention from scholars because they are among the earliest such pieces to have been written down. But the notation in Jacobus is ambiguous as to rhythm and metre, as well as to alignment of pitches between the voice parts in the polyphony.

• anon.: Ad sepulcrum beati Iacobi
• anon.: Ad superni regis decus
• anon.: Alleluia: Gratulemur et letemur
• anon.: Ascendens Ihesus in montem
• anon.: Benedicamus domino
• anon.: Clemens servulorum
• anon.: Congaudeant catholici
• anon.: Cunctipotens genitor
• anon.: Gratulantes celebremus festum
• anon.: Iacobe sancte tuum
• anon.: Iacobe servorum
• anon.: In hac die laudes
• anon.: Nostra phalanx plaudat leta
• anon.: O adiutor omnium seculorum
• anon.: Portum in ultimo
• anon.: Psallat chorus celestium
• anon.: Qui pius ac mitis
• anon.: Regem regum dominum
• anon.: Salve festa dies
• anon.: Venite omnes cristicole
• anon.: Vox nostra resonet