Legio XXX Ulpia Victrix ("Trajan's Victorious Thirtieth Legion") was a legion of the Imperial Roman army. Their emblems were the gods Neptune and Jupiter and the Capricorn. Ulpia is Trajan's own gens, while the cognomen "Victrix" means "victorious," and it was awarded after their valiant behaviour in the Dacian Wars. The legion was active until the disbandment of the Rhine frontier in the beginning of the 5th century.
The legion's first base camp was in the province of Dacia in the Danube frontier. It is likely that at least some of its legionaries took part in the Parthian campaigns of Trajan. In 122 they were moved to Colonia Ulpia Traiana (modern Xanten[3][4]) in Germania Inferior, where they remained for the following centuries. Their main tasks were public construction and police affairs.
In the 2nd century and the beginning of the 3rd century, units of the XXX Ulpia Victrix were allocated in Parthia, as well as Gaul, Mauretania and other Roman provinces, due to the peaceful situation in Germania Inferior. They fought in Antoninus Pious' campaigns in Mauritania.[5]
In the civil war of 193, XXX Ulpia Victrix supported Septimius Severus, who granted them the title of Pia Fidelis ("faithful and loyal").[4]
With the re-organization of the Roman Army (Constantius I Chlorus), the legions guarding the border lost their importance to the comitatus, the main, cavalry-based army behind the limes. The collapse of the Rhine frontier after 408–410 marked the end of the legion's history.
^ abcdeBenett, Julian (2008). The Legio XXX Ulpia Victrix Pia Fidelis And Severus' Expeditions Asiana and Mesopotamia. Romish-Germanisches Zentralmuseum.