The Gregorian chant of the Sarum Rite displaced Celtic chant. By the 9th century the Gallican rite and chant had effectively been eliminated, although not without local resistance. Charlemagne continued his father's policy of favoring the Roman Rite over the local Gallican traditions. The other plainchant repertories of the Christian West faced severe competition from the new Gregorian chant. In 885, Pope Stephen V banned the Slavonic liturgy, leading to the ascendancy of Gregorian chant in Eastern Catholic lands including Poland, Moravia, Slovakia, and Austria. From English and German sources, Gregorian chant spread north to Scandinavia, Iceland and Finland. Charlemagne, once elevated to Holy Roman Emperor, aggressively spread Gregorian chant throughout his empire to consolidate religious and secular power, requiring the clergy to use the new repertory on pain of death. Gregorian chant appeared in a remarkably uniform state across Europe within a short time. Gregory's authorship is popularly accepted as fact to this day. Gregory was portrayed dictating plainchant inspired by a dove representing the Holy Spirit, giving Gregorian chant the stamp of holy authority. This Frankish-Roman Carolingian chant, augmented with new chants to complete the liturgical year, became known as 'Gregorian.' Originally the chant was probably so named to honor the contemporary Pope Gregory II, but later lore attributed the authorship of chant to his more famous predecessor Gregory the Great. This Roman chant was subsequently modified, influenced by local styles and Gallican chant, and later adapted into the system of eight modes. In 785-786, at Charlemagne's request, Pope Hadrian I sent a papal sacramentary with Roman chants to the Carolingian court. According to Charlemagne, his father Pepin abolished the local Gallican rites in favor of the Roman use, in order to strengthen ties with Rome. During a visit to Gaul in 752-753, Pope Stephen II had celebrated Mass using Roman chant. Scholarly consensus, supported by Willi Apel and Robert Snow, asserts instead that Gregorian chant developed around 750 from a synthesis of Roman and Gallican chant commissioned by Carolingian rulers in France.

Bewerung's article in the Catholic Encyclopedia. Traditionalists point to evidence supporting an important role for Pope Gregory the Great between 590 and 604, such as that presented in H. Scholars debate whether the essentials of the melodies originated in Rome, before the 7th century, or in Francia, in the 8th and early 9th centuries. Other scholars, including Andreas Pfisterer and Peter Jeffery, have argued for an earlier origin for the oldest layers of the repertory. According to James McKinnon, the core liturgy of the Roman Mass was compiled over a brief period in the late 7th century. The Gregorian repertory was systematized for use in the Roman Rite. By these paths Gregorian chant came to dominate liturgical music in the West by the 8th Century. Others were abandoned when the region resolved to adopt what it considered a superior chant or liturgy. Some of these chants were suppressed by Roman pontiffs striving to establish a unified liturgy and music for the Church. From Milan came Ambrosian chant, named in honour of St Ambrose from Gaul, or what is now France, Gallican chant from Rome, Old Roman and Gregorian from England, the Sarum from the Church in the East, Syrian, Byzantine, Coptic, Ethiopian and Armenian.

In fact, the chant was composed and complete by the 7th Century, and altered little thereafter. Roman Spain produced Mozarabic chant, whose title refers to the Moorish rule over Spanish Christians after the invasion of 711. Following the legalisation of Christianity in 313, different forms and flavours of chant began to develop by region.

Unaccompanied singing has been part of the Christian liturgy since the earliest days of the Church. This single line of melody, called monophony, characterized music until about 1000 AD. Manuscripts date from ninth century and used a system of modes, specific patterns of whole and half steps. This music consisted of a single line of melody with a flexible rhythm sung to Latin words by unaccompanied male voices. The sacred music of the Gregorian Chant was also known as plainchant, or plainsong and named after Pope Gregory. Origins are traditionally are ascribed to the period of Pope Gregory I 590-604. Gregoran chants are a body of chants of the Roman Catholic Church, most of which are part of two liturgical rites, the Mass and the Offices.

Gregorian notation program