It is said that Charlemagne was friends with the Caliph Harun ar-Rashid. Is it possible? Does this not contradict Karl’s wars with Muslims?

Charlemagne fought with neighboring Muslims (with the Emirate of Cordoba in Spain), and he maintained good relations with the distant Baghdad Caliphate. (At the court of Karl, Harun ar-Rashid’s brother lived as an emigrant.)

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