Though he spent the last 40 years of his life serving the French Royal Chapel, Johannes Ockeghem apparently began his musical career in Antwerp in the 1440s. He forged a professional relationship during these years with the famous elder composer Gilles de Bins (dit Binchois), who was serving the Court of the Dukes of Burgundy—possibly even studying music under his tutelage. Near the occasion of Binchois' death in 1460, Ockeghem composed a moving Déploration (lament) for his colleague—Mort, tu as navré—and quite possibly at the same time composed a cyclic cantus firmus mass based on the tenor voice to Binchois' rondeaux De plus en plus. Taken together, the Déploration and the Mass present a touching and powerful act of homage.

Ockeghem seems to have known several different versions of Binchois' chanson, as the various movements of his Mass preserve slightly different readings of the tune. However, on the surface, the form of the Mass appears straightforward: the Tenor voice of the chanson model is used as the structural foundation of each mass movement, being sung in the Mass' Tenor voice at least once, with no transpositions. The opening four notes of the model always appear in audible long-notes, calling attention to the beginning of the cantus firmus, and strongly identifying the tune. However, Ockeghem does manipulate the cantus firmus in several interesting ways. First, he subverts the odd harmonic implications of Binchois' model to a more uniform Mixolydian mode for his Mass. Partly, this is accomplished by his own contrapuntal setting in the other voices, and partly by the appending of a cantus firmus "tag" to four movements; this tag not only repeats the characteristic first phrase, but more importantly cadences on the correct tone. It is also the case that he never gives the chanson tune the same way twice—the treatment rather forms a spectrum from broad and consistent embellishment (in the Kyrie) to nearly strict quotation (in Sanctus and Agnus Dei III).

Unfortunately, no copies of the Mass survive which are early enough to securely date it. Instead, versions exist in one Italian manuscript from the 1470s or 1480s, and in the lavish Ockeghem "retrospective" anthology from around 1500, the Chigi Codex. Stylistically, it shares some features with the composer's earlier mass music such as the Missa Caput and Missa l'Homme armé, as well as with the English music (such as the anonymous English Missa Caput, falsely attributed to Dufay) which achieved popularity on the Continent in the 1440s. The level of rhythmic density in the Mass is similar to the composer's earlier masses. But the freedom of cantus firmus elaboration and the palpable climax carefully constructed in the Agnus Dei III are forward-looking features.

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