surnamed Practextatus, and also Philologus, the latter of which surnames he assumed in order to indicate his great learning, was born at Athens, sand was one of the most celebrated grammarians at Rome, in the latter half of the first century B. C. He was a freedman, and was perhaps originally a slave of the jurist Ateius Capito, by whom he was characterized as a rhetorician among grammarians, and a grammarian among rhetoricians. He taught many of the Roman nobles, and was particularly intimate with the historian Sallust, and with Asinius Pollio. For the former he drew up an abstract of Roman history (Breviurium rerum omnium Romanarum), that Sallust might select from it for his history such subjects as he chose; and for the latter he compiled precepts on the art of writing. Asinius Polllio believed that Ateius collected for Sallust many of the peculiar expressions which we find in his writings, but this is expressly denied by Suetonius. The commentarii of Ateius were exceedingly numerous, but only a very few were extant even in the time of Suetonius. (Sueton. de Illustr. Grammat. 10; comp. Osann, Analecta Critic. p. 64, &c.; Madvig, Opuscula Academica, p. 97, &c.)
A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890