Flavius Mallius Theodorus (fl. c. 376–409) was a Roman politician and author of an extant treatise on metres, De metris, one of the best of its kind (H. Keil, Grammatici Latini, vi.). He also studied philosophy, astronomy and geometry, and wrote works on those subjects, which, together with his consulship, formed the subject of a panegyric by Claudian.[1]