We have them, they are called Paulvestites and Buchananites.
It seriously hurt Mediterranean civilization.
Within a short while one of the best places to live was out in the Arabian desert at the oasis called Mecca ~ and that was not all that good a place.
The development of small, local markets was a sign that civilization was returning to Western Europe. That came about some time after the creation of the local defense system called Feudalism. Took Western and Northern Europe about a thousand years to recover ~ I believe Michelangelo (1475-1564) was the first sculptor since the 400s to create a human-form statue as good as had been done by the ancient Romans and Greeks.
Not that statuary is the halmark of the best in civilization, but a thousand years without a good statue is definitely a sign that something serious was wrong, and it wasn't exactly marketing strategies!
The Chinese did their recovery in something like 300 years. They still get higher scores on IQ tests.