Does anyone know the origin of Gregorian hymn?

According to tradition, Pope Gregory I (reigned from 590 to 604) collected and sorted out hymns from all over the country for the purpose of unified management of the church, and compiled two anthologies of hymns, thus unifying the rituals and music used by the Roman church. But in fact, the main work of unifying Roman church rituals and hymns was carried out more than one hundred years later. In 789, Charlemagne of the Frankish Kingdom issued a decree urging the abolition of Gaul etiquette and the full acceptance of Roman hymns. In the following decades, Archbishop Frank revised and supplemented the Roman sacrament book, compiled new mass and daily lesson books, and formed worship ceremonies and hymns based on Roman tradition and incorporating Gaul factors. This is the basic content of the so-called Gregorian chant This kind of hymn spread to other regions and finally fed back to Rome, the birthplace.

Gregorian chant is a monosyllabic texture, and the melody is mainly progressive, without changing or modifying the sound. Free rhythm depends on the length of the sentence. Try to be quiet and detached emotionally and refuse secular passion. It is dedicated to Latin and is sung with pure human voice (that is, without instrumental accompaniment). Adopt the church model.