Islam, The Byzantine Empire, and Germanic Tribes

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…Franks penetrated German borders. The movement stopped for a while in the late 3rd century during the reigns of the emperors Diocletian and Constantine the Great, but it resumed under pressure from the non-Germanic Huns, who came out of Central Asia in the 4th century. In the 5th century the Germans occupied the whole Western Roman Empire. Over the next few hundred years, the Germanic tribes adopted Christianity and laid the foundations of medieval Europe.