Polybius

The first great historian of Rome was not Roman, nor did he write in Latin; he was Greek and employed that language. Polybius (202–120 B.C.E.) believed that Rome’s power derived from its institutions, most notably its constitution. Aristotelian political theories and Thucydides’ histories influenced Polybius greatly. Polybius lacked his forerunner’s political acumen, but his call for archival research shaped future historiography. Polybius would serve as a touchstone of later Roman historians, including Livy.

R. O’Brian Carter, “Roman historians,” in Encyclopedia of World History, ed. Marsha E. Ackermann et al. (New York: Facts On File, 2008), 1:393.