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..
Naturally the most obvious achievement of the Romans was their vast empire, which spread over three continents. It lasted for a long, long time. From 625 BC to AD 476 = 1101 years ! - And if one includes the eastern Roman empire which lasted until AD 1453 it would even be 2078 years ! In comparison the United States of America only exists since 1776 - less than 250 years.