The fifth century AD was a time of great changes in the Mediterranean world. In the early 400s, the Roman Empire ranged from the lowlands of Scotland to the Upper Nile and from Portugal to the Caucasus. It was almost at its widest extent, and although ruled by two emperors—one in the West and one in the East—it was still a single empire. One hundred years later, Roman control of Western Europe and Western North Africa had been lost.