Polybius (; , ; ) was a Greek historian of the Hellenistic period. He is noted for his work , which covered the period of 264–146 BC and the Punic Wars in detail. 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. 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. Early life Polybius was born around 200 BC in Megalopolis, Arcadia, when it was an active member of the Achaean League. The town was revived, along with other Achaean states, a century before he was born. Polybius' father, Lycortas, was a prominent, land-owning politician and member of the governing class who became strategos (commanding general) of the Achaean League. 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. In his early years, he accompanied his father while travelling as ambassador. He developed an interest in horse riding and hunting, diversions that later commended him to his Roman captors. 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. 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. This event often presaged election to the annual strategia (chief generalship). His early political career was devoted largely towards maintaining the independence of Megalopolis. Personal experiences Polybius' father, Lycortas, was a prominent advocate of neutrality during the Roman war against Perseus of Macedon. Lycortas attracted the suspicion of the Romans, and Polybius subsequently was one of the 1,000 Achaean nobles who were transported to Rome as hostages in 167 BC, and was detained there for 17 years. In Rome, by virtue of his high culture, Polybius was admitted to the most distinguished houses, in particular to that of Lucius Aemilius Paullus Macedonicus, the conqueror in the Third Macedonian War, who