This Mamertinus should not to be confused with the Claudius Mamertinus who composed a panegyric for the emperor Julian. To the author under consideration here scholars have attributed two discourses that were delivered in honor of the Augusti Maximian and Diocletian at Trier on 21 April of 289 AD and 21 July of (probably) 291 AD (Nixon-Rodgers; Lassandro). The attribution has been proposed on the basis of a statement from a single codex (London, British Library, Harley 2480), which claims that the second panegyric is a work eiusdem magistri Mamertini. The reservations of Seeck notwithstanding, this conclusion is also supported by the stylistic homogeneity of the two works, which can be seen chiefly in the author’s mode of addressing the emperors. Very little is known about the author of the panegyrics: he was probably a Gallic rhetorician from the area, received a solid historical and mythological education from a nearby scholar, and was perhaps affiliated with the imperial court. [A. Balbo; tr. C. L. Caterine].