The Octoechos as a liturgical concept which established an organization of the calendar into eight-week cycles, was the invention of monastic hymnographers at Mar Saba in Palestine and in Constantinople. It was formally accepted in the Quinisext Council of 692, which also aimed to replace the exegetic poetry of the kontakion and other homiletic poetry, as it was sung during the morning service (Orthros) of the cathedrals.

One reason, why another eight mode system was established by Frankish reformers during the Carolingian reform, was probably, that Pope Adrian I accepted the seventh-century Eastern reform for the Western Church as well during the 787 synod. The only evidence is an abbreviated chant book called “tonary”. It was simply a list of incipits of chants ordered according to the intonation formula of each church tone and its psalmody. Later also fully notated and theoretical tonaries had been written.

The Byzantine book Octoechos has originally been part of the sticherarion. It was one of the first hymn books with musical notation and its earliest copies survived from the 10th century. Its redaction follows the Studites reform, during which the sticherarion has been invented.  source: wikipedia.org

index: Musicology, Byzantine Music, Octoechos

Part of trilogy:

• Hagiopolitan Octoechos, Papadic Octoechos, Neobyzantine Octoechos