Battle of Syllaeum

Infobox Military Conflict
conflict=Battle of Syllaeum


caption=Byzantine ship using "Greek fire"
partof=the Muslim conquests
date=677
place=Sea of Marmara
result=Byzantine victory
combatant1=Roman (Byzantine) Empire
combatant2=Umayyad Caliphate
commander1=Unknown
commander2=Unknown
strength1=Unknown
strength2=Unknown
casualties1=Unknown
casualties2=Unknown

The naval Battle of Syllaeum took place in 677 near Syllaeum and was fought between the Arabs and the Byzantine Empire in coordination with a series of land battles in Anatolia and Syria.

The Arab fleet had continually harassed the Byzantine navy for five years, starting in 672. In 677 they launched raids along the coast of Anatolia, into the Sea of Marmara, and besieged Constantinople itself, while at the same time an army raided Anatolia. Coincidentally the Slavs were attacking Thessalonica by land, so that the Byzantine army was distracted on two fronts. Byzantine emperor Constantine IV sent his fleet to meet the Arabs near Syllaeum, and the Arab fleet was destroyed by Greek fire, a new Byzantine weapon that had been used for the first time only a few years before. As the Arabs retreated they were caught in a storm that sank nearly all of their ships. Meanwhile, the Byzantine army pursued the Arabs back to Syria and defeated them there. This ended the immediate Arab threat to eastern Europe, and peace lasted for almost 30 years.