Polyhistor, Alexander a Roman writer whose works have been used by the Church fathers, a native of Cotyemim in Phrygia, according to some, and of Miletus according to others, was a geographer and historian, who lived in the 7th century of Rome, and was taken prisoner by the Romans in the war of Sulla against Mithridates. Being purchased by Cornelius Lentulus, he was entrusted by him with the education of his children, and at last received his freedom. He then assumed the name of Cornelius, after that of his patron. He resided chiefly at Rome, and had a country-house at Laurentum, in which, having taken fire while he was there, he perished in the flames. He is often mentioned and quoted by Pliny the Elder, Diogenes Laertius, Clemens Alexandrinus, and Eusebius, as a man of very extensive learning, in consequence of which he was styled Polyhistor. He wrote a work in forty books, each book being the description of a distinct country. Stephanus Byzantinus mentions his account of Bithynia, Caria, Paphlagonia, Syria, Libya, Crete, and other countries. Clemens Alexandrinus quotes his Treatise on the Jews, of which Eusebius has inserted fragments in his "Chronography." Clemens Alexandrinus mentions another work of Polyhistor, on the Symbol of Pythagoras; and Cyril of Alexandria, in his work against Julian, quotes his authority on the early history of the world. Unfortunately none of Polyhistor's works have come down to us.