<P> The consular duties were of any type whatever: military defense, police work, public hygiene, assistance in civil disaster, health work, agriculture, and especially construction of public roads, bridges, aqueducts, buildings, and the maintenance of such . The soldiers were kept busy doing whatever service needed to be done: soldiering, manning vessels, carpentry, blacksmithing, clerking, etc . They were trained as required, but also previous skills, such as a trade, were exploited . They brought to the task and were protected by the authority of the state . </P> <P> The military's campaign history stretched over 1300 years and saw Roman armies campaigning as far east as Parthia (modern - day Iran), as far south as Africa (modern - day Tunisia) and Aegyptus (modern - day Egypt) and as far north as Britannia (modern - day England, south Scotland, and Wales). The makeup of the Roman military changed substantially over its history, from its early history as an unsalaried citizen militia to a later professional force, the Imperial Roman army . The equipment used by the military altered greatly in type over time, though there were very few technological improvements in weapons manufacture, in common with the rest of the classical world . For much of its history, the vast majority of Rome's forces were maintained at or beyond the limits of its territory, in order to either expand Rome's domain, or protect its existing borders . Expansions were infrequent, as the emperors, adopting a strategy of fixed lines of defense, had determined to maintain existing borders . For that purpose they constructed extensive walls and created permanent stations that became cities . </P> <P> At its territorial height, the Roman Empire may have contained between 45 million and 120 million people . Historian Edward Gibbon estimated that the size of the Roman army "most probably formed a standing force of three hundred and seventy - five thousand men" at the Empire's territorial peak in the time of the Roman Emperor Hadrian (117 − 138CE). This estimate probably included only legionary and auxiliary troops of the Roman army . However, Gibbon states that it is "not...easy to define the size of the Roman military with any tolerable accuracy ." In the late Imperial period, when vast numbers of foederati were employed by the Romans, Antonio Santosuosso estimated the combined number of men in arms of the two Roman empires numbered closer to 700,000 in total (not all members of a standing army), drawing on data from the Notitia Dignitatum . However, he notes that these figures were probably subject to inflation due to the practice of leaving dead soldiers "on the books" in order to continue to draw their wage and ration . Furthermore, it is irrespective of whether the troops were raised by the Romans or simply hired by them to fight on their behalf . </P> <P> Initially, Rome's military consisted of an annual citizen levy performing military service as part of their duty to the state . During this period, the Roman army would prosecute seasonal campaigns against largely local adversaries . As the extent of the territories falling under Roman suzerainty expanded, and the size of the city's forces increased, the soldiery of ancient Rome became increasingly professional and salaried . As a consequence, military service at the lower (non-staff) levels became progressively longer - term . Roman military units of the period were largely homogeneous and highly regulated . The army consisted of units of citizen infantry known as legions (Latin: legiones) as well as non-legionary allied troops known as auxilia . The latter were most commonly called upon to provide light infantry or cavalry support . </P>

Who influenced the way rome organized its army