<P> Roman camps followed a standard pattern for defense and religious ritual; in effect they were Rome in miniature . The commander's headquarters stood at the centre; he took the auspices on a dais in front . A small building behind housed the legionary standards, the divine images used in religious rites and in the Imperial era, the image of the ruling emperor . In one camp, this shrine is even called Capitolium . The most important camp - offering appears to have been the suovetaurilia performed before a major, set battle . A ram, a boar and a bull were ritually garlanded, led around the outer perimeter of the camp (a lustratio exercitus) and in through a gate, then sacrificed: Trajan's column shows three such events from his Dacian wars . The perimeter procession and sacrifice suggest the entire camp as a divine templum; all within are purified and protected . </P> <P> Each camp had its own religious personnel; standard bearers, priestly officers and their assistants, including a haruspex, and housekeepers of shrines and images . A senior magistrate - commander (sometimes even a consul) headed it, his chain of subordinates ran it and a ferocious system of training and discipline ensured that every citizen - soldier knew his duty . As in Rome, whatever gods he served in his own time seem to have been his own business; legionary forts and vici included shrines to household gods, personal deities and deities otherwise unknown . </P> <P> From the earliest Imperial era, citizen legionaries and provincial auxiliaries gave cult to the emperor and his familia on Imperial accessions, anniversaries and their renewal of annual vows . They celebrated Rome's official festivals in absentia, and had the official triads appropriate to their function--in the Empire, Jupiter, Victoria and Concordia were typical . By the early Severan era, the military also offered cult to the Imperial divi, the current emperor's numen, genius and domus (or familia), and special cult to the Empress as "mother of the camp ." The near ubiquitous legionary shrines to Mithras of the later Imperial era were not part of official cult until Mithras was absorbed into Solar and Stoic Monism as a focus of military concordia and Imperial loyalty . </P> <P> The devotio was the most extreme offering a Roman general could make, promising to offer his own life in battle along with the enemy as an offering to the underworld gods . Livy offers a detailed account of the devotio carried out by Decius Mus; family tradition maintained that his son and grandson, all bearing the same name, also devoted themselves . Before the battle, Decius is granted a prescient dream that reveals his fate . When he offers sacrifice, the victim's liver appears "damaged where it refers to his own fortunes". Otherwise, the haruspex tells him, the sacrifice is entirely acceptable to the gods . In a prayer recorded by Livy, Decius commits himself and the enemy to the dii Manes and Tellus, charges alone and headlong into the enemy ranks, and is killed; his action cleanses the sacrificial offering . Had he failed to die, his sacrificial offering would have been tainted and therefore void, with possibly disastrous consequences . The act of devotio is a link between military ethics and those of the Roman gladiator . </P>

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