Leo III
Leo III, also known as Leo the Isaurian, was a significant Byzantine emperor who reigned from 717 to 741. His early career was marked by military and diplomatic service in the northeastern Byzantine Empire, leading to his appointment as the military governor of Anatolikon. In a pivotal moment, he overthrew Emperor Theodosius III, entering Constantinople on March 25, 717, which marked the end of a tumultuous period of civil strife. Leo's leadership was crucial during the siege of Constantinople by Arab forces in 717, where his innovative use of Greek fire played a key role in repelling the attackers.
Following this victory, he focused on strengthening the empire's defenses against continuous Arab raids, particularly during the years 720 to 740, and engaged in military campaigns in regions like eastern Asia Minor and Armenia. He also instituted significant reforms, including the controversial policy of iconoclasm, which involved the prohibition of religious images, and took actions to assimilate Jewish populations. Leo's last major military success came at the Battle of Akroinon in 740, where he achieved a decisive victory over a large Arab force, temporarily curtailing their incursions. Leo III's reign is notable for both his military achievements and his efforts to consolidate imperial power amidst external threats.
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Leo III
Emperor
- Born: c. 685
- Birthplace: Kahramanmaraş, Turkey
- Died: June 18, 0741
- Place of death: Constantinople (now Istanbul, Turkey)
Full name: Emperor Leo III the Isaurian
Born: c. 680; Germanikeia, Commagene, Syria
Died: June 18, 741; Constantinople
Principal wars: Byzantine-Muslim Wars
Principal battles: Siege of Constantinople (717-718), Akroinon (740)
Military significance: After breaking an Arab siege of Constantinople, Leo stabilized the Byzantine state, reorganized the empire’s military defenses, and fought successfully against perennial Arab raids in eastern and central Asia Minor.
Leo III’s early years were spent as a diplomat and soldier in the northeastern Byzantine Empire. After being appointed military governor (strategos) of the military district of Anatolikon in Asia Minor (715), he overthrew Byzantine emperor Theodosius III, entering Constantinople on March 25, 717. This ended two decades of anarchy and civil war during which seven rulers rose and fell violently. Although Leo had been emperor for only a short time, Constantinople was prepared for the Arab attack of July, 717, when about 120,000 men and 1,800 ships under the leadership of Maslamah ibn ʿAbd al-Malik and Caliph Sulaymān. Greek fire, a petroleum mixture, kept the Muslim fleet at bay, and the naval blockade failed. The Arab army suffered through a harsh winter outside the city’s great walls and from the attacks of Bulgarians that Leo had rallied. The siege was lifted in August, 718.
From 720 to 740, Leo fought against Arab raids in eastern Asia Minor and Armenia, and against Cyprus (725). Caesarea was sacked in spring, 726. Leo reorganized the empire’s eastern military defenses and allied himself with the Bulgarian Khazars. He also invoked divine aid by outlawing religious images (iconoclasm), forcibly baptizing Jews, and updating the legal code. His last victory, at Akroinon (740), over 20,000 Arabs, temporarily halted their raids.
Bibliography
Scott, Roger, ed. The Chronicle of Theophanes Confessor. Oxford: Clarendon Press, 1997.
Treadgold, Warren. Byzantium and Its Army, 284-1081. Stanford, Calif.: Stanford University Press, 1995.
Whittow, Mark. The Making of Byzantium, 600-1025. Berkeley: University of California Press, 1996.