While UV rays can cause skin cancer, because skin cancer usually affects people after they have had children, it likely had little effect on the evolution of skin color because evolution favors changes that improve reproductive success.
The only problem was that I couldn't remember where I had heard that. In fact, I wasn't all that sure that I was right. I know that the Roman Empire lasted rougly 500 years but how about the Egyptians, the Chinese, the Ottomons, etc. I thought that it would be interesting to explore different empires and see how long they lasted. In another article, I talk about the definition of civilization..
History >> Ancient Rome. Rome ruled much of Europe around the Mediterranean for over 1000 years. However, the inner workings of the Roman Empire began to decline starting around 200 AD. By 400 AD Rome was struggling under the weight of its giant empire. The city of Rome finally fell in 476 AD. Rome reached its peak of power in the 2nd century around the year 117 AD under the rule of the great Roman emperor Trajan.