The tradition of eastern liturgical chant, encompassing the Greek-speaking world, developed even before the establishment of the new Roman capital, Constantinople, in 330 until its fall in 1453. Byzantine music is mostly derived from the early music of Syrian Christian communities, synthesized with Greek, Romans and Jewish elements. The Byzantine system of octoechos, in which melodies were classified into eight modes, is specifically thought to have been exported from Syria, where it was known in the 6th century, before its legendary creation by John of Damascus. It was imitated by musicians of the 7th century to create Arab music as a synthesis of Byzantine and Persian music, and these exchanges were continued through the Ottoman Empire until Istanbul today.