Polybius

Polybius ( /pəˈlɪbiəs/; c. 200–118 BC), Greek Πολύβιος) was a Greek historian of the Hellenistic Period noted for his work, The Histories, which covered the period of 264–146 BC in detail. The work describes in part the rise of the Roman Republic and its gradual domination over Greece. Polybius is also renowned for his ideas concerning the separation of powers in government, later used in Montesquieu's The Spirit of the Laws and in the drafting of the United States Constitution.