Notre-Dame school in the context of Polyphony

Classical music generally refers to the art music of the Western world, considered to be distinct from Western folk music or popular music traditions. It is sometimes distinguished as Western classical music, as the term "classical music" can also be applied to non-Western art musics. Classical music is often characterized by formality and complexity in its musical form and harmonic organization, particularly with the use of polyphony. Since at least the ninth century, it has been primarily a written tradition, spawning a sophisticated notational system, as well as accompanying literature in analytical, critical, historiographical, musicological and philosophical practices.

Rooted in the patronage of churches and royal courts in Europe, surviving early medieval music is chiefly religious, monophonic and vocal, with the music of ancient Greece and Rome influencing its thought and theory. The earliest extant music manuscripts date from the Carolingian Empire (800–887), around the time which Western plainchant gradually unified into what is termed Gregorian chant. Musical centers existed at the Abbey of Saint Gall, the Abbey of Saint Martial and Saint Emmeram's Abbey, while the 11th century saw the development of staff notation and increasing output from medieval music theorists. By the mid-12th century, France became the major European musical center: the religious Notre-Dame school first fully explored organized rhythms and polyphony, while secular music flourished with the troubadour and trouvère traditions led by poet-musician nobles. This culminated in the court-sponsored French ars nova and Italian Trecento, which evolved into ars subtilior, a stylistic movement of extreme rhythmic diversity. Beginning in the early 15th century, Renaissance composers of the influential Franco-Flemish School built on the harmonic principles in the English contenance angloise, bringing choral music to new standards, particularly the mass and motet. Northern Italy soon emerged as the central musical region, where the Roman School engaged in highly sophisticated methods of polyphony in genres such as the madrigal, which inspired the brief English Madrigal School.

France has a rich music history that was already prominent in Europe as far back as the 10th century. French music originated as a unified style in medieval times, focusing around the Notre-Dame school of composers. This group developed the motet, a specific musical composition. Notable in the high Middle Ages were the troubadours and trouvères soon began touring France, composing and performing many original songs. The styles of ars nova and ars subtilior sprung up in the 14th century, both of which focused on secular songs. As Europe moved into the Renaissance age, the music of France evolved in sophistication. The popularity of French music in the rest of Europe declined slightly, yet the popular chanson and the old motet were further developed during this time. The epicenter of French music moved from Paris to Burgundy, as it followed the Burgundian School of composers. During the Baroque period, music was simplified and restricted due to Calvinist influence. The air de cour then became the primary style of French music, as it was secular and preferred by the royal court.

The Magnus Liber or Magnus liber organi (English translation: Great Book of Organum), written in Latin, is a repertory of medieval music known as organum. This collection of organum survives today in three major manuscripts. This repertoire was in use by the Notre-Dame school composers working in Paris around the end of the twelfth and beginning of the thirteenth centuries, though it is well agreed upon by scholars that Leonin contributed a bulk of the organum in the repertoire. This large body of repertoire is known from references to a "magnum volumen" by Johannes de Garlandia and to a "Magnus liber organi de graduali et antiphonario pro servitio divino" by the English music theorist known as Anonymous IV. Today it is known only from later manuscripts containing compositions named in Anonymous IV's description. The Magnus Liber is regarded as one of the earliest collections of polyphony.

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.