Legio III Iulia Alpina: one of the legions of the later Roman empire. Its name means "the Julian Alpine legion.
This legion is mentioned in the late-antique text known as Notitia Dignitatum. It must have been the garrison of a province in the Italian diocese, most likely Alpes Cottiae (i.e., the region between Briançon and Susa).
Due to the fact that we have only one source mentioning this unit, the founder of the legion is not known. The element Julia, however, suggests that it was either Crispus, the son of the emperor Constantine I the Great, or Julius Constans, the emperor of the western half of the empire between 337 and 350. Since no other princes are credited with the building of legions, it is likely that I Iulia Alpina was founded by Constans.