The idea of the “Dark Ages” came from later scholars who were heavily biased toward ancient Rome.
In the years following 476 A.D., various Germanic peoples conquered the former Roman Empire in the West (including Europe and North Africa), shoving aside ancient Roman traditions in favor of their own. The negative view of the so-called “Dark Ages” became popular largely because most of the written records of the time (including St. Jerome and St. Patrick in the fifth century, Gregory of Tours in the sixth and Bede in the eighth) had a strong Rome-centric bias.
I agree because Migration period, also called Dark Ages or Early Middle Ages, the early medieval period of western European history—specifically, the time (476–800 ce) when there was no Roman (or Holy Roman) emperor in the West or, more generally, the period between about 500 and 1000, which was marked by frequent warfare
