Gaius Asinius Quadratus (fl. 248) was a Greek historian of Rome and Parthia in the 3rd century. Felix Jacoby in the Fragmente der griechischen Historiker provides the thirty remaining fragments of his work. Most derive from the dictionary of Stephanus of Byzantium. The Suda tells us that his work Chilieteris ("The Millennium") covered the period from the founding of Rome to the reign of Alexander Severus. He also wrote a Parthika, presumably a narrative of the Parthian campaigns of the preceding century. Some scholars attribute to him a Germanika, as well, although this is debated. All of his works were in Greek.
The "thousand years" of Quadratus' title has been explained in various ways. Jacoby argues that Quadratus unusually dated the founding of Rome to the first Olympiad in 776. Zecchini, on the other hand, claims that Quadratus used the traditional dating of the founding of Rome and intended the work to extend to 248, when Philip the Arab celebrated the 3rd millennium, dying before its completion.
Asinius is the nomen of the gens Asinia of ancient Rome. He was the son of Gaius Julius Asinius Quadratus, brother of Gaius Asinius Rufus (born c. 160) and Gaius Asinius Quadratus Protimus (born c. 165), Proconsul of Achaea c. 211 or in 220, children of Gaius Asinius Nicomachus (born c. 135) and wife and cousin Julia Quadratilla (born c. 145) (or perhaps Asinia Marcellina, descendant of the family of Gaius Asinius Pollio), and grandchildren of Gaius Asinius Rufus (c. 110 - after 136), a notable in Lydia in 134 and 135 who became a Roman Senator in 136, and wife Julia.