What was the initial reaction of Christian states to the early Muslim invasions? | AskHistorians Archive Observer

What was the initial reaction of Christian states to the early Muslim invasions?

by AceBalistic

Such as the Arab invasions of the Sassanid empire, Byzantine Syria, Egypt and North Africa.

Libertat

More can be said about this, but you might find some elements of answers in these previous posts.

How did more distant European Christian states react to the Islamic expansion of the 7th and 8th centuries? ( u/Libertat)
What did the Byzantines think about Islam when they first heard about it? ( u/Shlin28)
What was the reaction across Christendom to the conquest of Jerusalem and the Holy Land by the Rashidun Caliphate in 637? ( u/Shlin28)