Orthodox Byzantine music is the medieval sacred chant of all Christian churches following the Eastern Orthodox rite. This tradition, principally encompassing the Greek-speaking world, developed in Byzantium from the establishment of its capital, Constantinople, in 330 until its con- quest in 1453. It is undeniably of composite origin, drawing on the artistic and technical productions of the classical age and on Jewish music, and inspired by the plainsong that evolved in the early Christian cities of Alexandria, Antioch, and Ephesus. In common with other dialects in the East and West, Byzantine music is purely vocal and exclusively monodic. Apart from the acclamations (polychronia), the texts are solely designed for the several Eastern liturgies and offices. The most ancient evidence suggests that hymns and Psalms were originally syllabic or near-syllabic in style, stemming, as they did, from pre-okto␣ch congregational recitatives. Later, with the development of monasticism, at first in Palestine and then in Constantinople, and with the augmentation of rites and ceremonies in new and magnificent edifices (such as Hagia Sophia), trained choirs, each with its own leader (the protopsáltes for the right choir; the lampadários for the left) and soloist (the domestikos or kanonarch), assumed full musical responsibilities. Consequently after ca. 850 there began a tendency to elaborate and to ornament, and this produced a radically new melismatic and ultimately kalophonic style.