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His early political career was devoted largely towards maintaining the independence of Megalopolis. This event often presaged election to the annual strategia (chief generalship). In either 169 BC or 170 BC, Polybius was elected hipparchus (cavalry officer) with the intention of fighting for Rome during the Third Macedonian War. In 182 BC, he was given quite an honor when he was chosen to carry the funeral urn of Philopoemen, one of the most eminent Achaean politicians of his generation. He developed an interest in horse riding and hunting, diversions that later commended him to his Roman captors. In his early years, he accompanied his father while travelling as ambassador. Consequently, Polybius was able to observe first hand during his first 40 years the political and military affairs of Megalopolis, gaining experience as a statesman. Polybius' father, Lycortas, was a prominent, land-owning politician and member of the governing class who became strategos (commanding general) of the Achaean League. The town was revived, along with other Achaean states, a century before he was born. Polybius was born around 200 BC in Megalopolis, Arcadia, when it was an active member of the Achaean League. Walbank (1909–2008), who published studies related to him for 50 years, including a long commentary of his Histories and a biography.
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The leading expert on Polybius for nearly a century was F. Polybius is important for his analysis of the mixed constitution or the separation of powers in government, his in-depth discussion of checks and balances to limit power, and his introduction of "the people", which influenced Montesquieu's The Spirit of the Laws, John Locke's Two Treatises of Government, and the framers of the United States Constitution. He is noted for his work The Histories, which covered the period of 264–146 BC and the Punic Wars in detail. 118 BC ) was a Greek historian of the Hellenistic period. Polybius ( / p ə ˈ l ɪ b i ə s/ Greek: Πολύβιος, Polýbios c. Virtually all of subsequent Western philosophy and historical inquiry including: Cicero, Diodorus, Strabo, Livy, Plutarch, Arrian, Machiavelli, John Locke, Montesquieu, John Adams, Edmund Burke, Joseph De Maistre, Charles Joseph Minard, Ortega y Gasset
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