Polybius
![The [[stele]] of [[Kleitor]] depicting Polybius, [[Hellenistic art]], 2nd century BC, [[Museum of Roman Civilization]]<ref>John Ma. (2013). ''[https://books.google.com/books?id=u3LfaRlHLfwC&dq=Polybios+Stele+Kleitor&pg=PA282 Statues and Cities: Honorific Portraits and Civic Identity in the Hellenistic World]''. Oxford: Oxford University Press. {{ISBN|978-0-19-966891-5}}, pp 281-282.</ref>](https://upload.wikimedia.org/wikipedia/commons/c/c8/Stele_des_Polybios.jpg)
Polybius's ''Histories'' is important not only for being the only Hellenistic historical work to survive in any substantial form, but also for its analysis of constitutional change and the mixed constitution. Polybius's discussion of the separation of powers in government, of checks and balances to limit power, and his introduction of "the people", all influenced Montesquieu's ''The Spirit of the Laws'', John Locke's ''Two Treatises of Government'', and the framers of the United States Constitution.
The leading expert on Polybius for nearly a century was F. W. Walbank (1909–2008), who published studies related to him for 50 years, including a long commentary of his ''Histories'' and a biography.
Polybius was a close friend and mentor to Scipio Africanus the Younger, and had a lasting influence on his decision making and life. Provided by Wikipedia