Complex sentence: The Barbarian tribes from "Germania" kept penetrating deeper into the Roman territory, some of these tribes were the Osthrogoths, Visigoths, Vandals and Franks.
Split into simpler sentences: The Barbarian tribes from "Germania" kept penetrating deeper into the Roman territory. Some of these tribes were the Osthrogoths, Visigoths, Vandals and Franks.