Legio XV Primigenia Roman Standard

The Legio XV Primigenia was a legion of relatively late foundation, created by the emperor Caligula in AD 39 together with its “twin” XXII Primigenia, and dedicated to the goddess Fortuna Primigenia, particularly revered at court. Initially intended for the great Germanic offensive planned by the princeps, it crossed the Alps in the autumn of 39 to be deployed along the Rhine, in Germania, where it remained for the whole of its brief existence.

Its main castrum was Castra Vetera, near today’s Xanten, a strategic hub for controlling the Germanic tribes and the river routes.

During the Year of the Four Emperors, the XV Primigenia sided with Vitellius, taking part in his campaigns against Galba and then against Otho, confirming the strong political weight of the Rhine frontier legions. Back at Castra Vetera, it was caught up in the Batavian revolt of 69–70, when the Batavi, exploiting the civil chaos, besieged the camp. Despite the dispatch of reinforcements, the XV Primigenia, together with the V Alaudae, was forced to surrender in March 70 and was subsequently annihilated, being formally disbanded under Vespasian.