What gave the notion of a great usurpation of Roman lands by the barbarians is that we find in the laws of the Visigoths and the Burgundians that these two peoples had two-thirds of the lands ; but these two-thirds were taken only in certain sections that were assigned to them.
Gundebald says in the law of the Burgundians that his people at its establishment received two-thirds of the lands,  and it is said in the second supplement to this law that they would no longer give more than half to any who might come into the country.  Therefore not all the lands had been divided up between the Romans and the Burgundians.
We find the same expressions in the texts of these two statutes : therefore they explain each other ; and as we cannot understand the second as a global division of lands, neither can we give that meaning to the first.
The Franks acted with the same moderation as the Burgundians ; they did not despoil the Romans through the whole range of their conquests. What would they have done with so much land ? They took the lands that suited them, and left the rest.