>>15486659Muslims conquered scraps - by the 7th century the Byzantines and Persians had depleted their forces via constant warfare. They were weak. Most of the land the Muslims "conquered" was only guarded by tiny garrisons - not actual armies.
When the Muslims finally ran into a true, primed, battle-hardened people (the Franks) they got their asses handed to them. They obviously couldn't believe it and tried invading France again and once more got destroyed.
