Legio I Adiutrix Roman Standard

Legio I Adiutrix was a legion “born at sea” and destined to serve for a long time on the Danube frontiers of the Roman Empire.

Created in AD 68, it was formed from the sailors of the Misenum fleet, at a time of deep crisis for Nero’s regime and then during the Year of the Four Emperors, fighting initially for Galba and Otho. After Otho’s defeat at Bedriacum, it passed into the service of Vespasian, taking part in the suppression of the Batavian revolt and being stationed at Mogontiacum, on the Rhine, to defend Germania Superior. Under Domitian it was engaged against the Chatti and then in the first Dacian wars, before being permanently transferred to Pannonia, where it became one of the pillars of the Danube defences.

Under Trajan and his successors the legion fought in the Dacian and Parthian campaigns and in the Marcomannic wars under Marcus Aurelius, and supported Septimius Severus in the civil war of 193–197, earning the honorific titles of Pia Fidelis. In late antiquity I Adiutrix is still attested between Aquileia and Brigetio, in Pannonia, where its traces fade only in the 5th century.