Apart from the fact that Charlemagne built his empire on military conquest, he also formed a allegiance with the Roman Catholic Church.
Charlemagne of Charles was the Emperor of the Romans from 800. It should be noted that during the early Middle Ages, he united the majority of Western and Central Europe.
Charlemagne built his empire not only on military conquest but also on his union with the Roman Catholic Church. He was pivotal to the spread of Christianity.
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