Another interesting point about the Roman military is that there was no standing army during the Republic, troops were only raised as needed. It could be for an extended campaign that would take several years, but at the end of the campaign, the legions would be disbanded - a major social issue was land for the demobilized veterans in the late Republic after the property qualifications for military duty were lifted. Our society could use some Roman virtue about now. Too damned many free riders on the few who serve voluntarily.