Some history books are talking of an invasion from the barbarians but the reality's more grey. Barbarians were already in the landscape for a long time. As a matter of fact, by the end of the west empire, most of the army, including leaders, was made of barbarians. The "invasion" was in fact the arrival of big groups of people, fleeing themselves from what was probably more of an invasion this time : the Huns.

Yes, some tensions and conflicts probably occured in the process, but it was not the bloody invasion depicted in our school books.