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How did Leo III defend Constantinople against the Arab siege?
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Leo III
Leo III, gold solidus from Constantinople, 717–741.
Emperor Leo III successfully defended Constantinople against the Arab siege of 717–718 through a combination of strategic military actions and environmental factors. His defense was bolstered by the following key elements:
- Greek Fire: Leo utilized Greek fire, an igneous petroleum-based mixture that could not be extinguished with water, to inflict significant damage on the Arab fleet.12
- Bulgarian Assistance: A Bulgarian army, led by Tervel, joined forces with Leo to launch a massive offensive against the invading Arab troops, ultimately defeating them and contributing to the successful defense of the city.34
- Environmental and Tactical Factors: The defense was aided by a severe winter, desertions within the Arab fleet, and the effective use of the city's fortifications, which Leo had repaired.1
These combined efforts compelled the Arab commander, Maslamah ibn ʿAbd al-Malik, to abandon the siege, marking a decisive check to Arab expansionism and preventing the establishment of an Arab bridgehead in southeastern Europe.1