Who was Polybius, and how did he become Scipio Africanus the Younger's friend?

Polybius was a prominent Greek historian who became a significant influence on the life and character of the Roman general Scipio Africanus the Younger.

He originally arrived in Italy as one of a thousand Achaean leaders who were deported and detained without trial. Scipio and his brother intervened by persuading the Roman authorities to allow Polybius to remain in Rome, where he subsequently became a close friend and mentor to the two young men.1

Under Polybius's guidance, Scipio was encouraged to pursue the traditional Roman noble goals of honor, glory, and military success, while also focusing on personal morality and temperance during a period of declining social standards. Their bond was enduring; Polybius accompanied Scipio on various military campaigns, including the siege of Carthage in 146 BCE, and the two continued to discuss political matters together for many years.12