When Maurice Sully erected the current Cathedral of Notre-Dame,
Paris was one of the major cultural centres of Europe. Just a stone’s throw away from the Ile de la Cité, the monastery of Saint-Victor, and later the collège universitaire, founded by canon Robert de Sorbon (1257), contributed greatly to this influence. Students were drawn from all over Europe and, when they returned to their home countries, they passed on the knowledge they had learnt in Paris. It is for this reason that an English musician remarked in around 1275 on the intense musical activity that enlivened the Cathedral. His highly valuable account comes to us through the musicologist Edmond de Coussemaeker, who baptised him Anonyme IV (Anonymous IV) in a work from the mid 19th century. The posthumous contribution of this anonymous musician gave rise to the concept of a "Notre-Dame school", the setting for one of the most dramatic revolutions in the history of music: the advent of polyphony.
Polyphony is the art of superimposing several different voices, in contrast to the monody that until then was the norm. To consider the musicians of Notre-Dame as its inventors would be inaccurate. For one or two centuries, monks had become accustomed to improvising descants (fourth or fifth voice) alongside the plainchant melodies that they sang. However, it was the Parisian masters who stimulated the development of this new art, composing pages of an exceptional beauty that fascinated the whole of Europe and soon led to the founding of a school. In many countries, from the Pontifical Chapel to the English Royal Chapel and the major European cathedrals, this new style was adopted. However, for a century, nowhere else did polyphony achieve such a level of perfection as in Paris.
The first master of this "Notre-Dame school" was the Magister cantor
Albertus Parisiensis, Adam successor in 1192. His name appeared, along with
those such as Fulbert de Chartres, in the Codex Calixtinus kept at the
Cathedral of Compostella. This was the first manuscript to break the anonymity in which until then cathedral cantors were held. Nevertheless, it is another name that is remembered as belonging to the "father" of this movement: Magister Leoninus, otherwise known as Léonin (ca. 1135- ca. 1210). It was he who gave his letter patent to the emerging organum and conductus (conduit) genres, and gave them their written and measured form. The organum consists of a plainchant melody played out very slowly (the cantus firmus), over which
several faster, melismatic (including several notes per syllable) voices are laid in a contre-chant, in other words the organ voices. As for the conduit, this is a free composition, without a liturgical cantus firmus. Léonin, active in the last quarter of the 12th century, only composed two voice pieces. His successor, Pérotin, active until 1230, modernised the organas of Léonin and composed more complex, original works, with up to four voices. Anonyme IV explains: "Léonin was a major organa composer, who wrote the Grand Livre d’organa on the Gradual and Antiphonal melodies to make the liturgical service more striking. This book was in use until the time of Pérotin, who abbreviated it and composed many and better clausules, as he was an excellent composer of descants and better than Léonin".
The fourth major figures of this period, known as the "Notre-Dame school", is Philippe le Chancelier, chancellor of the cathedral from 1217 to his death, in 1236. He was one of the initiators of the motet, which became one of the major polyphonic genres up to the present day. It began as a derivative of the two voice organum. Certain, particularly ornate sections (or clausules) were isolated and words (possibly secular and in French)were placed over the organ voice’s singing, according to the trope technique, with one syllable per note, to make it easier to remember. This is where the word motet comes from, from the French "petit mot", or small word. This produced a two voice work, one playing out in long note-values a fragment of plainchant melody and the other presenting a much faster chant with a different text. The technique developed, quickly moving on to three voices, each possibly with a different text.
For several decades, the Grand Livre of Léonin and Pérotin provided many composer throughout Europe, and of course in France, with motets, including in particular the successors of Léonin and Pérotin at Notre-Dame, such as Robert de Sabillon or Francon de Paris, who it is generally agreed was none other than the famous theorist Francon de Cologne, active in the second half of the 18th century. In the middle of the 18th century, the texts of the two upper voices already no longer necessarily had a semantic link between them, and the content, which became a mere musical pretext, was usually performed by an instrument. Then, towards the end of the century, the motet became an independent genre – the flagship genre of the musical period known as the Ars Antiqua – and ceased to base itself on pre-existing clausules.
The motet poems were not composed at random. They often formed a gloss of the words of the Latin plainchant, which meant they could be included in the liturgy. Some motets and conducti had an openly moral or political content. These included the Mundus a mundicia by Philippe le Chancelier, and the In veritate comperi by Guillaume d’Auvergne, who was fighting against corruption in the clergy. The conducti poems were often a mixture of the sacred and the profane and some of these conducti became part of the festivities accompanying certain grandiose celebrations given at Notre-Dame, with banquets, singing and dancing, such as Nicholai presuli (for Saint-Nicolas) and Hac in die salutari (for New Year).
A text dating from around 1220 describes the sumptuous liturgies that took place in the new cathedral. On big occasions, all sorts of draperies and tapestries were hung and the nave and the choir and eight major festival saw the cathedral decked out to its full, including Christmas, Easter, Pentecost, the Ascension, the Purification, the Birth of Mary, the festival of Saint-Denis and the church’s Consecration. This was when the music reached its magnificent height and Graduals and Hallelujahs were performed with two, three or even four voices. The most extraordinary ceremonies were held during the week of Christmas, with which even Easter week could not compete. Christmas at Notre-Dame in fact consisted of a complete cycle of festivities. As well as the Nativity, there was the Circumcision and the festivals of Saint John and Saint Stephen. Almost all the organas mentioned from 1198 to 1200, in particular the famous four voice organas attributed to Pérotin by Anonyme IV, concern this period of the liturgical year.
It seems that there was no loft organ at the time when Léonin and Pérotin were making the name Notre-Dame famous Europe-wide. If they had pipe instruments, they could only have been fairly basic portable organs designed to accompany the plainchant melody hugely drawn out by the tenor voice. As for the title optimus organista, which Anonyme IV awarded to Léonin, this mean nothing other than "excellent organa composer".