LEO the Deacon. — Byzantine chronicler, born at Kaloc near Tmolus in 950; Skylitzes, in the preface to his History, calls him L. the Asian, while Cedrenus calls him L. of Caria. As a young man, he was in Constantinople; having been made a deacon, he followed Emperor Basil II the Bulgar-Slayer in the war against the Bulgarians (986); he was taken prisoner by the enemy during the siege of Triaditza, the ancient Sardica (Sofia).
He wrote Historiae libri X covering the years 959 to 975 (ed. B. Hase, Paris 1819; PG 117, 655-926), divided into three periods: the Romans against the Arab corsairs of Crete; the war in Asia; and the war against the Bulgarians and Russians. Leo’s style is akin to that of contemporary Byzantine chroniclers such as Agathias and Theophylact. The information is provided to him by eyewitnesses to the events.
Notable are his descriptions of the Arabs and the Bulgarians; good are his accounts of the reigns of Nicephorus Phocas. The history, which was not completed, was probably written around 992.