All subsequent Greek and Roman writers on the same subject made this work their text-book (the emperors Mauricius and Leon did little more than express in the corrupt style of their age what they found in Onosander, whom Leon calls Onesander), and it is even still held in considerable estimation. Count Moritz of Saxony professed to have derived great benefit from the perusal of a translation of it. Onosander appears to have lived about the middle of the first century after Christ. His work is dedicated to Q. Veranius, who is generally supposed to be identical with the Q. Veranius Nepos who was consul in A. D. 49. Onosander also remarks in his preface that his work was written in time of peace. It might very well have been written, therefore, between A. D. 49 and A. D. 59. If the consul of A. D. 49 was the person to whom the work was dedicated, it would agree very well with all the other data, that this Veranius accompanied Didius Gallus into Britain, and died before the expiration of a year.

Onosander was a disciple of the Platonic school of philosophy, and, according to Suidas, besides his work on tactics, wrote one Περὶ στρατηγημάτων (unless, as some suppose, the words τακτικα περὶ στρατηγημάτων in Suidas are a description of one and the same work, the one still extant), and a commentary on the Republic of Plato. The two latter have perished. In his style he imitated Xenophon with some success. Nothing further is known of his personal history. It is conjectured that he must himself have been engaged in military service.