Charlemagne became king of the Franks when his brother died in 771 and quickly set about a widespread campaign of military expansion throughout Europe. Charlemagne was staunchly Catholic and forced peoples in invaded lands to convert. He quickly imposed himself over the Lombards in northern Italy, forcing them to submit to him and gaining the title King of the Lombards in 774. He first invaded the Saxon lands in the west in 773, but repeated rebellions over the next 30 years would see constant fighting to impose Frankish power and Christianity. In 800, in recognition of his continued loyalty and support of the papacy during times of danger, Charlemagne was crowned Emperor of the Romans by Pope Leo III. This put Charlemagne’s empire in direct competition with the Byzantines who saw the Eastern Roman Emperor as the rightful successor to the throne.
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