The Oxford History of Western Music, Pt. 3

• The Kyrie is a chant from the Franco-Roman Mass, derived from earlier forms of Congregational singing. The earliest sources of Kyries were little books called Kyriale. They contained two versions of each melody, a syllabic version along with a melismatic version. There is evidence to suggest that both verions were in usage, rather than one developing out of the other. If this is the case, it seems likely that the syllabic version was used as a mnemonic device to remind singers of the correspondence between notes and syllables, while the melismatic version was a guide to the intricate melody of the chant. It was this need to convey all of this information at once that could well have led to the development of the staff.