Pérotin in the context of Peter (given name)

The Notre-Dame school or the Notre-Dame school of polyphony refers to the group of composers working at or near the Notre-Dame Cathedral in Paris from about 1160 to 1250, along with the music they produced.

The only composers whose names have come down to us from this time are Léonin and Pérotin. Both were mentioned by an anonymous English student, known as Anonymous IV, who was either working or studying at Notre-Dame later in the 13th century. In addition to naming the two composers as "the best composers of organum," and specifying that they compiled the big book of organum known as the Magnus Liber Organi, he provides a few tantalizing bits of information on the music and the principles involved in its composition. Pérotin is the first composer of organum quadruplum—four-voice polyphony—at least the first composer whose music has survived, since complete survivals of notated music from this time are scarce.

Anonymous IV is the designation given to the writer of an important treatise of medieval music theory. He was probably an English student working at Notre Dame de Paris, most likely in the 1270s or 1280s. Nothing is known about his life. His writings survive in two partial copies from Bury St Edmunds; one from the 13th century, and one from the 14th.

Along with Johannes de Garlandia and Franco of Cologne, whose work precedes his, Anonymous IV's writings are the main source for understanding the Notre Dame school of polyphony. He wrote about Léonin and Pérotin, thereby assigning names to two of the composers of the music of the Notre Dame school who otherwise would have been anonymous. Léonin and Pérotin are among the earliest European composers whose names are known. Although they probably died at least fifty years earlier, he described them as still famous and part of the living tradition.

Ars antiqua, also called ars veterum or ars vetus, is a term used by modern scholars to refer to the Medieval music of Europe during the High Middle Ages, between approximately 1170 and 1310. This covers the period of the Notre-Dame school of polyphony (the use of multiple, simultaneous, independent melodic lines), and the subsequent years which saw the early development of the motet, a highly varied choral musical composition. Usually the term ars antiqua is restricted to sacred (church) or polyphonic music, excluding the secular (non-religious) monophonic songs of the troubadours, and trouvères. Although colloquially the term ars antiqua is used more loosely to mean all European music of the 13th century, and from slightly before.

The term ars antiqua is used in opposition to ars nova (meaning "new art", "new technique" or "new style"). The transition from ars antiqua into ars nova is not clearly defined, recent interpretation has described the transition to be a gradual evolution rather than an abrupt revolution with the period being between the 13th–14th centuries.