ビザンティン聖歌
Byzantine music (Greek: Βυζαντινή Μουσική) is the music of the Byzantine Empire composed to Greek texts as a ceremonial, festival or church music. Greek and foreign historians agree that the ecclesiastical tones and in general the whole system of Byzantine music is closely related to the ancient Greek system. It remains the oldest genre of extant music, of which the manner of performance and (with increasing accuracy from the 5th century onwards) the names of the composers, and sometimes the particulars of each musical work's circumstances, are known.