Students of the Roman military may be excused for drawing incorrect impressions about the stability of Roman legions during the Late Republic and Early Empire. Writing on military historiography, John Keegan observed, "Certainly no military institution of which we have detailed, objective knowledge has ever been given the monumental, marmoreal, almost monolithic uniformity of character which classical writers conventionally ascribe to the Legions."1 Keegan may have been waxing rhetorical, but his characterization is not far off the mark, and still applies as much to modern military historians as it does to "classical writers." The modern image of the Roman military remains remarkably idealistic.2 Many readers still think of the Roman military not only as a success, but also as a military machine, rolling inexorably over the Mediterranean world with its efficient training and brutal discipline. Despite its reputation for rigid efficiency and coercive discipline, there were outbreaks of indiscipline and unrest in the Roman military. This fact of military life was only natural. Every institution that relies on ordered, collective action for success is occasionally subject to disturbances by its participants, even the military. In the military these disturbances took the form of indiscipline and unrest. What makes military unrest more dangerous to stability is that soldiers receive training in working together effectively under stress and in the efficient use of weapons. The potential for organized violence and the military's importance as an institution are why military unrest was such a threat to the stability of any state. The Roman military was undeniably successful, but we also know that military unrest occurred and was more common than has been thought in the past. Every Roman commander who spent much time actively campaigning