We cannot tell when that decisive moment occurred; all we can know are its first preserved fruits.
One of the earliest is a Kyrie–Gloria–Credo–Sanctus set somewhat shakily attributed to Dunstable, based
on a tenor derived from Da gaudiorum praemia (“O grant the prize that brings joy”), a responsory for
Trinity Sunday (the Sunday after Pentecost). It is bound up with the family history of the Henrys of
England and was very likely first performed at the wedding of Henry V and Catherine of Valois, his joyful
prize and daughter of the French King Charles VI, which took place on Trinity Sunday, 2 June 1420. The
same Mass seems to have been performed again at another royal occasion, the Paris coronation of Henry
VI in 1431.
There, already, is a clue to the original purpose of the cyclic organization of the Ordinary: the use of a
symbolic or emblematic tenor uniting its various sections renders the Ordinary “proper” to an occasion.
The common cantus firmus acts like a trope, a symbolic commentary on the service. It was, or could be, a
most potent device for insuring that there would be no separation of church and state.
More secure is the attribution to Leonel Power of a four-part Ordinary complex (a pair, so to speak,
of traditional pairs: Gloria/Credo and Sanctus/Agnus Dei) all based on a tenor derived from the Marian
antiphon Alma Redemptoris Mater. This composition, found only in northern Italian manuscripts copied
around 1430–1435, is one of the best witnesses to the prestige of English music at the time and the
leadership that English composers were exercising over musical developments on the continent.
Unlike Dunstable, his (probably) somewhat younger contemporary, Leonel Power does not seem to
have made much of an international career. It was his music that traveled. Except for a brief French
sojourn between 1419 and 1421 with his employer the Duke of Clarence (brother of Henry V, in whose
campaign the Duke was participating), the composer spent his whole professional life in England, first as
tutor to the choristers in the Duke’s household chapel, and later as a member of the fraternity of Christ
Church, Canterbury, where he died, probably aged around seventy, in 1445. One of his duties at the
Canterbury church was to lead the choir that sang special votive services in the “Lady chapel,” and it was
presumably for this choir that he composed, on a suitable Marian hymn, the Mass that, because it was so
widely circulated in manuscript copies, now looms so large in history.
Unifying the sections of Mass cycles on the basis of common tenors meant laying out a foundation in
advance and building from the ground up. This architectonic conception had previously been the special
distinguishing characteristic of the motet. And indeed, that genre was the source of the idea, even as the
motet itself was undergoing change in the fifteenth century, a change that implied a “lowering” of its style.
What happened, in effect, was that the rigidly conceived, highly structured style if the isorhythmic motet—
the “high style” or stylus gravis of the fourteenth century—passed from the motet into the domain of the
cyclic Mass, which was potentially a kind of isorhythmic motet writ large, with five or so discrete
sections replacing the multiple color-talea cursus of old.
All the characteristics that mark a “high” style in the Ciceroniansense—weightiness, loftiness,
nobility, vouchsafed by a highly rationalized, “artificial” idiom of “unnatural” intensity and complexity—
became the property of the Mass, even as the motet loosened up under another strain of English influence
to become more “naturally” declamatory, more personally expressive, more texturally flexible, thus
assuming the position of a “middle” style. To appreciate this shift, keep Dunstable’s Quam pulchra es
(Ex. 11-19) in mind as a “middle style” foil to accompany and contrast with the brief account that follows
of Leonel’s Mass on Alma Redemptoris Mater.
The arbitrarily strict, the artificial, and the unnaturally formal—hallmarks of the high style—are very
conspicuous in the fashioning and the treatment of Leonel’s cantus firmus. Ex. 12-2 a shows Alma
Redemptoris Mater as it is found in the Liber usualis, the modern chant book, with the major divisions as
extracted by Leonel for the purposes of his Mass setting, amounting to roughly half of the original melody,
indicated with bars and Roman numerals. These divisions do not conform at all to the given (text-based)