Holy Alliance (Umayyad World)

The Holy Alliance was a military alliance organized by Pope Gregory III in 733 to halt the expansion of Islam into Europe. The alliance contained nearly all the nations and nation-states in Europe at the time, and initially led successful campaigns in Anatolia against the expansion of the Umayyad and Abbasid caliphates, but eventually, following the end of the Muslim Civil War in 787, the Islamic armies captured and destroyed Byzantium and much of the Frankish Kingdom, as well as the Balkan Peninsula.

The alliance initiated the Grand War in 738, after the Umayyad Caliphate resumed massive attacks on the Byzantine Empire, in which the entire Christian and Muslim worlds were engulfed in war with one another for years. Following an Islamic "victory" in the Grand War, the Holy Alliance was dissolved and replaced with the Holy League, formed among the remaining Christian states in central and northern Europe to reconquer eastern Europe from the Umayyads and the Emirate of Narbonne and Parisian Kingdom.