Organizing of the music group in the cathedral was such that the polyphonic vocal choir singing musicians were set behind the tapestries whereas the organ was placed in the nave. In the cathedral, polyphony and organ music were reserved for solemn occasions at a time when acoustics were not well developed. Composition of music and poetry was a culture that prevailed in the cathedral among its canons and dignitaries. At Notre-Dame, this culture became intertwined as its construction progressed. Choral polyphony is a musical genre which was introduced in the 15th century in the Western church music culture. A group of Parisian aristocrats, known as trouvères, became known for their poetry and songs. In the late 12th century, a school of polyphony was established at Notre-Dame. The Gallic music of the churches of Gaul was replaced by the plain songs traced to Rome. Prior to the ninth century there were no written manuscripts of liturgy related to music. The music of the religious schools became popular outside the churches the melodies of chants were adapted for popular songs, and sometimes popular song melodies were adapted for church use. Its choir had twenty-five persons, both men and boys, who were taught chanting and vocal techniques. Ī second important music school was established at the Sainte-Chapelle, the royal chapel on the Île de la Cité. The motet became so popular that it was used in non-religious music, in the court and even by musicians and singers on the streets. In the 13th century, the monks of the Notre Dame school developed an even more complex form, the motet, or "little word" short pieces for two or three voices, each chanting different words, and sometimes in different languages. Another famous teacher at the Notre Dame school, Pérotin, composed for four different voices, with highly complex rhythms, blending all the voices together in ways never heard before. The Archdeacon Albert of the Notre Dame school became famous for composing the first known work for three voices, each chanting a different part at the same time. When the new Cathedral of Notre Dame de Paris was constructed, the Notre Dame school became famous for its innovations in vocal counterpoint, or polyphony. Large monasteries were founded on the Left Bank at Saint-Germain-des-Prés, Sainte-Geneviève, and Saint-Victor, which taught the art of religious chanting, adding more elaborate rhythms and rimes. The Emperor Charlemagne had founded a school at the first cathedral of Notre Dame in 781, whose students chanted during the mass and the court also had a school, the schola palatina, which traveled wherever the imperial court went, and whose students took part in the religious services at the Royal Chapel. In the Middle Ages, music was an important part of the ceremony in Paris churches and at the royal court. Kyrie from Messe de Nostre Dame composed by Guillaume de Machaut, about 1350 Music of medieval Paris The cathedral schools and choral music 13.7 The Bastille Opera and the City of Music.13.5 Classical music-the Orchestre de Paris.13.3 Music from the Maghreb, Africa and the Caribbean.13.1 Jazz clubs of Saint-Germain-des-Pres.12 World War II-occupation and liberation.11.5 The radio, phonograph, and the musical film.11.4 The music hall-Mistinguett and Josephine Baker.11.3 The arrival of jazz-the Hot Club de Paris.11.2 Dance-the Ballets Russes and Ida Rubinstein.11.1 Classical music-Ravel, Satie and Stravinsky.10.6 Links to music of the Belle Époque.10.5 Dance-the Bal-musette, the cakewalk, the can-can and the tango.10.4 Diaghilev, Stravinsky and the Ballets Russes.10.3 The café concert, the music hall and the cabaret.9.5 The Cirque-Napoleon, concerts in the parks, and the Paris Expositions.9.3 The Théâtre Italien, the Théâtre-Lyrique, and the Opera-Comique.9.2 Hervé, Offenbach and the Opéra Bouffes.9.1 The Imperial Opera-Verdi and Wagner.8.6 Popular music-street musicians and goguettes.8.4 Balls, Concerts-Promenades and the romance.8.2 The Conservatory and the symphony orchestra.8.1 The Royal Academy, Opéra-Comique and Théâtre-Italien.8 Music in Paris under Louis Philippe (1830-1848).7.3 Popular music-the Goguette and the political song.7 Music during the Restoration (1815–1830).6 Music during the First Empire (1800-1814).5.3 Pleasure gardens, cafés chantants and guinguettes.5 The music of revolutionary Paris (1789–1800).4 18th century-the opera, the comic opera, and the salons.3 17th century - royal court music, ballet and opera.2.3 New instruments and the guild of instrument-makers.2.2 Music and the first theater companies.2.1 The Reformation and religious music.2 Music of Renaissance Paris (16th century).1.1 The cathedral schools and choral music.