Greek Fire Saves Constantinople From the First Arab Siege
A secret incendiary weapon burns the Arab fleet and keeps Byzantium's capital from falling
Quick facts
- First used
- 678 CE
- Credited inventor
- Kallinikos of Syria
- Emperor
- Constantine IV
- Effect
- Ended the first Arab siege of Constantinople
What happened
As the Umayyad Caliphate pressed its expansion against Byzantium, Arab fleets blockaded Constantinople for years in the 670s CE, wintering on the nearby peninsula of Cyzicus and renewing attacks on the city's fortifications each spring. In 678 CE the Byzantines deployed a new weapon for the first time in battle: Greek Fire, a highly flammable liquid invented by a Christian refugee named Kallinikos who had fled Muslim-held Syria for Constantinople in 668 CE. Sprayed under pressure or launched in catapulted bombs, the substance set enemy ships and fortifications ablaze and could not be extinguished with water. Its use against the Arab fleet destroyed large portions of it and forced the caliphate to lift the siege.
Why it matters
Greek Fire became the most valuable weapon in the Byzantine arsenal for the next seven centuries, and later Emperor Romanos II declared its formula, along with the imperial regalia and royal princesses, one of three things that must never fall into foreign hands. Its closely guarded secret was kept in Byzantine hands alone until the technology of naval warfare eventually made it obsolete.
How we know
The World History Encyclopedia's dedicated article on Greek Fire describes its 678 CE first use, its inventor Kallinikos, and its centuries-long status as a state secret, drawn from Byzantine military and chronicle sources.
Sources
- World History Encyclopedia. Greek Fire: The Byzantines' Secret Weapon · Reputable sourceworldhistory.org · The domain "worldhistory.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- World History Encyclopedia. Constantine IV · Reputable sourceworldhistory.org · The domain "worldhistory.org" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
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