Legio I Adiutrix Roman Vexillum

Legio I Adiutrix was a legion "born at sea" and destined to serve for a long time on the Danubian borders of the Roman Empire.

Created in 68 AD, it was formed from the sailors of the Misenum fleet, at a time of severe crisis for the Neronian regime and then during the Year of the Four Emperors, initially fighting for Galba and Otho. After Otho's defeat at Bedriacum, it entered Vespasian's service, participating in the suppression of the Batavian revolt and being stationed in Mogontiacum, on the Rhine, to defend Upper Germania. 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 Danubian defense.

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