What were some less civilized people that attacked the Roman empire?

Uncivilized people who attacked the Roman Empire were known as Barbarians. After numerous invasions from Barbarians and various other groups, the Roman Empire ultimately collapsed in 476 A.D. One prominent group of barbarians were the ancient Germanic peoples. Many of these were first captured by invading Roman legions and became part of the empire, even as citizens and soldiers. Many also did not, and were primary enemies that helped bring down Rome.