In S Italy, and in Spain, the Islamic conquest, though eventually pushed back, changed what the West would have been otherwise. Muslims were the outside modifier to Europe. Jews were in contrast, the inside modifier to Europe. This starts with the conquest of the Middle East by Islam, before they go to S Italy and Spain ...
https://www.youtube.com/watch?v=LdqFW8RWfQk
This conventional narration is wrong about the actual first 100 years of Islam, as the qibla analysis has shown, that Mecca then wasn't Mecca now, and that the mythical and legendary aspects of Muhammad and the first Caliphs can't be ignored.