Leo III the Isaurian
Byzantine emperor who ended anarchy and banned icon veneration.
Wikipedia / Wikimedia Commons
Leo III the Isaurian (c. 685 – 18 June 741), also known as the Syrian, was the first Byzantine emperor of the Isaurian dynasty, reigning from 717 until his death. He ended the Twenty Years' Anarchy, a period of instability and rapid imperial succession between 695 and 717, and halted the territorial losses the Byzantines had suffered during the 7th century. He successfully defended the Empire against the Umayyad siege of Constantinople and is known for forbidding the veneration of icons.
- born
- c. 685 in Germanikeia (modern Kahramanmaraş, Turkey)
- died
- 18 June 741
- field
- Byzantine Emperor
- nationality
- Byzantine (of Syrian origin)
- known_for
- Ending the Twenty Years' Anarchy, defending Constantinople from the Umayyads, and initiating iconoclastic policies
Lore & Background
Leo III was born Konon in Germanikeia, within northern Syria, and spoke Arabic as his native language. After serving as a diplomat and military commander, he overthrew Emperor Theodosius III and was crowned on 25 March 717. Immediately faced with the second Arab siege of Constantinople, he used Greek fire and allied with the Bulgarians to force the Umayyads to abandon the siege in August 718. He later suppressed rebellions in Sicily and by the deposed Anastasius II, and consolidated the empire's administration.
Reader's Guide
Leo III's reign marked a turning point for the Byzantine Empire, ending decades of internal chaos and external decline. His successful defense of Constantinople preserved the empire from collapse, while his administrative and military reforms stabilized the frontiers. His iconoclastic edicts (726–729) sparked lasting religious conflict, leading to revolts and the resignation of Patriarch Germanus. The transfer of ecclesiastical authority from Rome to Constantinople in parts of Italy and Illyricum further strained relations with the papacy. His legacy includes the centralization of imperial power and the militarization of the empire, though his iconoclasm remained controversial.
Did You Know?
- Leo III's original name was Konon, and he spoke Arabic as his native language.
- The nickname 'the Isaurian' is considered a misnomer by most modern scholars, possibly a textual error or a delegitimizing label.
- He forced the baptism of all Jews and Montanists in the empire in 722.
- The 740 Constantinople earthquake damaged the Walls of Constantinople, which Leo restored by raising city taxes by 8⅓ percent.
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