Polybius (ca. 203-120 BC, Greek) was a Greek historian of the Mediterranean world famous for his book called "The Histories" or "The Rise of the Roman Empire," covering in detail the period of 220-146 BC. He is also renowned for his ideas of political balance in the government, which was later used in the drafting of the United States Constitution. Wikipedia
The definitive Wikipedia entry for Polybius. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Polybius
