why might cities have shrunk drastically in western europe shrank somewhat in the byzantine empire but prospered and grew in the muslim caliphates

After the fall of the Western Roman Empire, cities in Western Europe shrank dramatically and in some cases vanished altogether. In the Byzantine Empire, cities also shrank, although not to the extent that they had in Western Europe. In the Muslim world, however, cities did not shrink, and indeed, cities in the Middle East and North Africa prospered in what historians often refer to as a golden age of Islam.

Why might cities have shrunk drastically in Western Europe, shrank somewhat in the Byzantine Empire, but prospered and grew in the Muslim caliphates? Your answer needs to be at least two paragraphs long and you need to respond to at least two other students’ posts. Remember to cite any outside sources!