Everywhere we come upon a college of decuriones or civic magistrates,—composed of a greater or lesser number of members elected from among the wealthiest citizens or supplemented from the government departments of the city,—which gradually absorbed all authority and constituted the supreme governing body of the municipium, under the presidency of two or four chief magistrates (
The rigid rule of the monarchy and the exact organisation and strict supervision of the municipal authorities obviated the danger of revolts and serious disturbances among the populace, and Italy (the capital and its vicinity only excepted) was clear of garrisons. The naval forces stationed at Ravenna and Misenum served to protect the coast and maritime towns, and in the hour of danger a sufficient army could always be summoned from Dalmatia and Pannonia. The imperial guard of prætorians (of which three cohorts consisting of one thousand men apiece were quartered in Rome, and the other six in the neighbouring towns) was mainly composed of Italians. It shared with a German and Batavian troop of horse the duty of guarding the palace and the sacred person of the monarch.
It is in the nature of every monarchical system of government to bring all conditions into congruity, to smooth over the diversities which prevail among its subjects, and to impress the stamp of uniformity upon the whole state. This was the case in the organisation of both provinces and municipalities, for in spite of modifications of legal status they were all cut upon the same pattern and organised according to definite classes. The same thing took place in financial affairs and taxation. During the republican period Rome and Italy had enjoyed a privileged position, and foreign countries had been exploited for the advantage of the dominant race. The principate, on the contrary, endeavoured to bring about an equalisation of duties and contributions as well as of privileges. The customs dues, which formerly applied only to subject countries, were extended to Italy under the monarchy, part of the proceeds being allotted to the public revenue and part to the Italian municipalities; the property tax, from which Italy had been exempt in the later days of the republic, was likewise introduced throughout the empire on the basis of the census or rating of property; an excise duty was levied for the fiscus (imperial privy purse) upon all articles imported into Italy for sale, amounting to one per cent. of the price, and two or even four per cent. in the case of slaves; the twentieth part of every inheritance which did not fall by right to the next of kin had to be paid into the military treasury, and a tax was imposed on the manumission of slaves.
If the revenues of the state were increased by these means under the empire the improvement was mainly due to sounder financial administration, to the abolition of revenue farming for the regular land tax and property tax in subject countries, and to the strict control exercised over the tax-gatherers; and according to Gibbon’s estimate the annual revenue secured must have amounted to at least fifteen to twenty million pounds sterling [$75,000,000 to $100,000,000]. Even if five million pounds were spent on the army and navy, if the distributions of corn to the poor of the city swallowed a few millions more, and the salaries of the imperial officials in Rome and the provinces and the police expenditure disposed of no inconsiderable sum, the surplus was none the less sufficient to provide for the erection of magnificent buildings, to cover the empire with a network of highroads, to satisfy the popular love of spectacles by gorgeous entertainments, and to rejoice the hearts of citizens and soldiers with gifts and feasts.