Key Facts
- Duration
- Approximately 4 years (674–678)
- Key weapon
- Greek fire, used to destroy the Arab navy
- Umayyad Caliph
- Mu'awiya I
- Byzantine Emperor
- Constantine IV
- Arab base of operations
- Peninsula of Cyzicus, near Constantinople
Strategic Narrative Overview
Arab forces installed a loose blockade around Constantinople, using Cyzicus as a winter base and launching renewed attacks each spring against the city's walls. The siege persisted for several years until Emperor Constantine IV deployed Greek fire, a newly developed liquid incendiary weapon, devastating the Arab fleet. Byzantine land forces simultaneously defeated the Arab army in Asia Minor, compelling the besieging forces to withdraw.
01 / The Origins
Following the Muslim civil war of 656–661, Caliph Mu'awiya I consolidated power over the Umayyad Caliphate and resumed aggressive expansion against the Byzantine Empire. Seeking a decisive blow, he targeted Constantinople itself, the Byzantine capital. Arab fleets first secured coastal bases along Asia Minor in 672–673, establishing the logistical foundation for a sustained assault on the empire's most fortified city.
03 / The Outcome
The Arab withdrawal ended the siege, and a peace treaty was signed shortly after. A subsequent Muslim civil war further weakened the Caliphate, allowing Byzantium a brief period of regional ascendancy. The outcome was considered the first significant Arab military defeat in half a century of expansion and provided the Byzantine Empire a critical respite after prolonged warfare and territorial losses.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Mu'awiya I.
Side B
1 belligerent
Constantine IV.
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.