Gnaeus Pompeius Trogus[n 1] also anglicized as was a Gallo-Roman historian from the Celtic Vocontii tribe in Narbonese Gaul who lived during the reign of the emperor Augustus. He was nearly contemporary with Livy.
Pompeius Trogus's grandfather served under Pompey in his war against Sertorius. Owing to Pompey's influence, he was able to obtain Roman citizenship and his family adopted their patron's praenomen and nomen Gnaeus Pompeius. Trogus's father served under Julius Caesar as his secretary and interpreter. Trogus himself seems to have been a polymath.
His principal work, however, was his 44-volume Philippic Histories and the Origin of the Whole World and the Places of the Earth (Historiae Philippicae et Totius Mundi Origines et Terrae Situs) which had as its principal theme the Macedonian Empire founded by but functioned as a general history of all of the parts of the world which fell under the control of Alexander the Great and his successors, with extensive ethnographical and geographical digressions. Trogus began with Ninus, legendary founder of Nineveh, and ended at about the same point as Livy (AD 9). The development of the East from the Assyrians to the Parthians is given extensive coverage while early Roman history and the history of the Iberian peninsula is briefly glossed in the last two books. The Philippic Histories is indebted to earlier Greek historians such as Theopompus (whose own Philippica may have suggested Trogus's title), Ephorus, Timaeus, and Polybius. On the grounds that such a work was beyond the powers of Gallo-Roman, it has generally been assumed that Pompeius Trogus did not gather his material directly from these Greek sources but from an existing compilation or translation by a Greek such as the Universal History compiled by Timagenes of Alexandria.
Pompeius Trogus's idea of history was more exacting than that of Sallust and Livy, whom he criticized for their habit of putting elaborate speeches into the mouths of the characters of whom they wrote.
The original text of the Philippic Histories has been lost and is preserved only in excerpts by other authors (including Vopiscus, Jerome, and Augustine) and in a loose epitome by the later historian Justin. Justin aimed only to preserve the parts he felt most important or interesting about Pompeius Trogus's work, with the last recorded event being the recovery of Roman standards from the Parthians in 20 BC. In the manuscripts of Justin's works, however, a separate series of summaries (prologi) of the original work have been preserved. Even in their present mutilated state the works are often an important authority for the ancient history of the East.
Pompeius Trogus's works on animals and plants were extensively quoted in the works of Pliny the Elder.