Sederunt principes V. Adiuva me domine is one of only three surviving four-part organa. It is one of two attributed to the medieval French composer Perotinus (fl c.1200). It is notated in the very early mensural rhythmic notation called rhythmic modes, which causes it to be in what we would consider compound meter. Sederunt principes forms the gradual for the Mass of the feast of St Stephen, which is celebrated on December 26. It is possible that Eudes de Sully, bishop of Paris, alluded to this piece in an edict. On Christmas 1199, Eudes established the observance of the feasts of Circumcision and St Stephens day, in Notre Dame referring in the course of the decree to the 'clerks who sing at Mass the gradual or alleluia in triple organum'. The other 4-voice organum by Perotin, Viderunt omnes is the gradual for the Mass on the feast of Circumcision. Viderunt Omnes V. Notum fecit dominum Viderunt Omnes V. Notum fecit dominum is one of only three surviving four-part organa. It is one of two attributed to the medieval French composer Perotinus (fl c.1200), who is also known as Pérotin. Following the tradition of tropes and sequences in the 10th and 11th centuries, organa were composed for feast days. They were used in both the Offices (small services held throughout the day) and the Ordinary of the Mass (The part of the mass that could use changeable texts). Viderunt Omnes forms the gradual for the Mass of the feast of Circumcision, (the circumcision being Christ's) which is celebrated on January 1. In a description of performance practice, Eudes de Sully, Bishop of Paris wrote that the gradual and alleluia of the Mass of the feast of Circumcision should be sung "either in triple or quadrule organum ... by four men walking in procession"

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