Publius Flavius Vegetius Renatus, commonly referred to simply as Vegetius, was a writer of the Later Roman Empire. Nothing is known of his life or station beyond what he tells us in his two surviving works: Epitoma rei militaris (also referred to as De Re Militari), and the lesser-known Digesta Artis Mulomedicinae, a guide to veterinary medicine.
The latest event alluded to in his Epitoma rei militaris is the death of the Emperor Gratian (383); the earliest attestation of this work is a subscriptio by one Flavius Eutropius, writing in Constantinople in the year 450, which appears in one of two families of manuscripts, suggesting that a bifurcation of the manuscript tradition had already occurred. Despite Eutropius' location in Constantinople, the scholarly consensus is that Vegetius wrote in the Western Empire. Vegetius dedicates his work to the reigning emperor, who is identified as Theodosius, ad Theodosium imperatorem, in the manuscript family that was not edited in 450; the identity is disputed: some scholars identify him with Theodosius the Great, while others follow Otto Seeck and identify him with the later Valentinian III, dating the work 430-35.