One of the main factors in deciding the issue was the Roman command of the sea which Carthage never felt able to challenge seriously. Another was the larger citizen body of Rome, and the friendly relations between herself and her federate allies. This, with the system of universal military service, gave her a citizen soldiery which in morale and numbers was superior to the armies of Carthage. As long as Hannibal was in Italy Rome kept from year to year upwards of 100,000 men in the field. Once only, after the battle of Cannae, was she unable to replace her losses by the regular system of recruiting and had to arm 8000 slaves who were promised freedom as a reward for faithful service. On the other hand, Carthage had to raise her forces from mercenaries or from subject allies. As her resources dwindled the former became ever more difficult to obtain, while the demands made upon the latter caused revolts that cost much effort to subdue. It required the personality of a Hannibal to develop an esprit de corps and discipline such as characterized his army in Italy. A third factor was the absence in the Roman commanders of the personal rivalries and lack of coöperation which so greatly hampered the Carthaginians in Spain and in Sicily. Still one must not be led into the error of supposing that the Carthaginians did not display tenacity and patriotism to a very high degree. The senatorial class especially distinguished itself by courage and ability, and there are no evidences of factional strife hampering the conduct of the war. The Romans overcame the disadvantage of the annual change of commanders-in-chief by the use of the proconsulship and pro-praetorship often long prorogued, whereby officers of ability retained year after year the command of the same armies. This system enabled them to develop such able generals as Metellus and the Scipios.
The cost of maintaining her fleet and her armies taxed the financial resources of Rome to the utmost. The government had to make use of a reserve fund which had been accumulating in the treasury for thirty years from the returns of the 5% tax on the value of manumitted slaves, and the armies in Spain could only be kept in the field by the generosity and patriotism of several companies of contractors who furnished supplies at their own expense until the end [pg 88]of the war. An additional burden was the increased cost of the necessities of life and the danger of a grain famine, caused by the disturbed conditions in Italy and Sicily and the withdrawal of so many men from agricultural occupations. In 210 the situation was only relieved by an urgent appeal to Ptolemy Philopator of Egypt, from whom grain had to be purchased at three times the usual price. However, this crisis passed with the pacification of Sicily in the next year.
Furthermore, a heavy tribute had been levied upon the man power of the Roman state. The census list of citizens eligible for military service fell from about 280,000 at the beginning of the war to 237,000 in 209; and the federate allies must have suffered at least as heavily. The greatest losses fell upon the southern part of the peninsula. There, year after year, the fields had been laid waste and the villages devastated by the opposing armies, until the rural population had almost entirely disappeared, the land had become a wilderness, and the more prosperous cities had fallen into decay. From the effects of these ravages southern Italy never recovered.