In 1453, when Byzantium fell to the Turks, Pope Pius II called for a new Crusade. Crusading fervor resounded strongly in the neo-chivalric culture of the Duchy of Burgundy. One unexpected fruit of this climate may have been the elevation of a little chanson rustique, a popular ditty about the "armed man" ("L'Homme armé"), into an internationally popular song, and the inspiration for one of the most famed clusters of compositions in the Renaissance. Either Robert Morton or Antoine Busnois, both singers at the court of the Burgundian Duke Charles the Bold, included the L'homme armé tune in a satirical quodlibet (a song that presents other well-known tunes in humorous or clever combinations), Il sera pour vous, and sometime in the late 1460s the first of a long line of masses took the tune as cantus firmus. All told, some 40 masses in the late fifteenth and sixteenth centuries would be composed on L'homme armé. Although probably not the first to be composed, that by Antoine Busnois is apparently seminal to the ongoing tradition. The intricacies in his treatment of the L'homme armé cantus firmus line, coupled with the excitement of his often richly imitative counterpoint in the outer voices, give a freshness and novelty to the piece. Guillaume Dufay may have quoted Busnois in his Missa l'homme armé, and Jacob Obrecht models his own mass directly on that of Busnois. A splendid set of six such masses, preserved anonymously in a manuscript presented to the King of Naples by the Burgundian Court, betray a structural and symbolic debt to Busnois, and his name has been suggested as composer for them as well. Some facets of Busnois' cantus firmus treatment do seem quite unusual. Whereas the L'homme armé tune divides neatly into three segments, he divides it instead into two parts in the Kyrie and Agnus Dei, and at seemingly random places in the inner three movements. His compositional artifice transposes the tenor melody down a fourth in the Credo, using a Latin canon (a written instruction in the music telling performers how to assemble the parts); in the Agnus Dei he gives the cantus firmus in augmented inversion. Though he adds no ornamentation to the cantus firmus, leaving its jaunty rhythms and horn call of falling fifths clearly audible, different mensuration signs (time signatures) produce different paces in the tenor voice relative to the other three. The Neapolitan theorist Johannes Tinctoris, in fact, though he praised Busnois as one of the most literate composers of the day, criticized his choices of mensuration in this piece. These idiosyncrasies, in fact, result in part from the composer's conscious adoption of a hyper-rational program within the Mass. Medieval music theory credits Pythagoras with the discovery of musical consonance, and the expression of intervals and chords by means of simple ratios. Busnois' selection of mensurations allows him to manipulate the length of the various movements of the Mass so that they not only relate in groups of threes (the perfect number of the Trinity), but also present ratios which symbolically correspond to the Pythagorean intervals. The lone exception is the Et incarnatus, which at the literal center of this Mass, lasts 31 tempora (units of time). Thirty-one happens to be the exact number of knights invested with membership in Charles the Bold's Order of the Golden Fleece, inaugurated in 1468. The importance of the same number to several of the anonymous Naples L'homme armé masses suggests a strong connection between the entire group and the Burgundian Court, again centering on the remarkable person of Antoine Busnois.

© Timothy Dickey, Rovi