The Gods of the Imperial Roman Army
Although the Roman soldier might worship many gods, writes Colin Martin, the State religion was an integral part of every military establishment.
Wherever he was stationed within the vast periphery of the Imperial frontiers, a Roman soldier owed his direct allegiance to the State, to the Emperor, and to the national gods of Rome. The religion of the Roman army was skilfully channelled in support of these unifying ideals, so that a soldier could at once identify himself as an active participant in the great destiny of Rome, and draw spiritual comfort from the belief that in so participating he was fulfilling a sacred obligation. Piety, indeed, was regarded as much a soldierly virtue as courage or skill at arms. Thus, in its own right, religion was as important a factor in the success of the Roman military machine as was its superiority in organization, discipline, equipment and tactics.
From the earliest days of the Republic, the Romans had conceived religion as a solemn contract between themselves and their gods; a belief that Roman power sprang from, and was maintained by, Roman piety. The proper worship of these gods was therefore a matter of urgent concern at all times, and nowhere more than in the army, for whom the gods were, above all, the guarantors of that military achievement on which the security of the State ultimately depended.