Byzantine music (Greek: Βυζαντινή μουσική) is the music of the Byzantine Empire. Originally it consisted of songs and hymns composed to Greek texts used for courtly ceremonials, during festivals, or as paraliturgical and liturgical music. The ecclesiastical forms of Byzantine music are the best known forms today, because different Orthodox traditions still identify with the heritage of Byzantine music, when their cantors sing monodic chant out of the traditional chant books such as the Sticherarion, which in fact consisted of five books, and the Irmologion. Byzantine music did not disappear after the fall of Constantinople. Its traditions continued under the Patriarch of Constantinople, who after the Ottoman conquest in 1453 was granted administrative responsibilities over all Eastern Orthodox Christians in the Ottoman Empire. During the decline of the Ottoman Empire in the 19th century, burgeoning splinter nations in the Balkans declared autonomy or autocephaly from the Patriarchate of Constantinople. The new self-declared patriarchates were independent nations defined by their religion. In this context, Christian religious chant practiced in the Ottoman Empire, in, among other nations, Bulgaria, Serbia and Greece, was based on the historical roots of the art tracing back to the Byzantine Empire, while the music of the Patriarchate created during the Ottoman period was often regarded as "post-Byzantine". This explains why Byzantine music refers to several Orthodox Christian chant traditions of the Mediterranean and of the Caucasus practiced in recent history and even today, and this article cannot be limited to the music culture of the Byzantine past. The Byzantine chant was added by UNESCO in 2019 to its list of Intangible Cultural Heritage "as a living art that has existed for more than 2000 years, the Byzantine chant is a significant cultural tradition and comprehensive music system forming part of the common musical traditions that developed in the Byzantine Empire". Imperial age 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 was influenced by Hellenistic music traditions, classic Greek music as well as religious music traditions of Syriac and Hebrew cultures. 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