In the town territories the body of the decurions or magistrates of the town were responsible for the total sum of the taxes to which the estates and farms of the district were liable. The general control of the taxation in each province was entirely in the hands of the provincial governor, but the collection was carried out by officials appointed by the decurions of each town.74 These collectors handed over their receipts to the compulsor, who represented the provincial governor, and he brought pressure to bear upon those who had not paid.75
Heavy taxes fell upon all classes of the population when a new Emperor came to the throne and on each fifth anniversary of his accession. On these occasions it was the custom to distribute a donation to the army, and a large sum of gold and silver was required.76 The senators contributed an offertory (aurum oblaticium).77 The decurions of every town had to scrape together gold which was presented originally in the form of crowns (aurum coronarium). Finally a tax was imposed on all profits arising from trade, whether on a large or a petty scale. This burden, which was known as Five-yearly Contribution (lustralis collatio) or Chrysargyron (“Gold and Silver”) fell upon prostitutes as well as upon merchants and shopkeepers, and was felt as particularly oppressive. It is said that parents sometimes sold their children into slavery or devoted their daughters to infamy to enable them to pay it.78
The chief immunity which senators enjoyed was exemption from the urban rates. Besides the aurum oblaticium, and the obligation of the wealthier of their class to fill the office of consul or of praetor, they were liable to a special property tax paid in specie. It was commonly known as the follis79 and was scaled in three grades (1 lb., 1/2 lb., and 1/4 lb. of gold according to the size of the property. Very poor senators paid seven solidi80 (£4, 8s. 6d.).
The senators, however, were far from being overtaxed. Most of them were affluent, some of them were very rich, and proportionally to their means they paid far less than any other class. In Italy the income of the richest was sometimes as high as £180,000, in addition to the natural products of their estates which would fetch in the market £60,000. Such revenues were exceptional, but as a rule the senatorial landed proprietors, who had often estates in Africa and Spain as well as in Italy, varied from £60,000 to £40,000.81
Besides the yield of all these taxes, which ultimately fell on agricultural labour, the Emperor derived a large revenue from custom duties,82 mines, state factories, and extensive Imperial estates. We have no figures for conjecturing the amount of their yield.
The central treasury, which represented the fisc of the early Empire, was presided over by the Count of the Sacred Largess.83 All the senatorial taxes, the aurum oblaticium, the collatio lustralis, the custom duties, the yield of the mines and of the public factories, that portion of the land-tax which represented the old tributum, the land-tax which was paid by the colons on the Imperial domains,84 all flowed into this treasury. The Count of the Largess administered the mint, the customs, and the mines.
Besides the central treasury, at the Imperial residence in each half of the Empire, there were the chests (arcae) of the Praetorian Prefects. These ministers, though they had lost their old military functions, were paymasters of the forces. They were responsible not only for regulating the amount but also for the distribution of the annona. As much of the annona collected in each province as was required for the soldiers stationed there was handed over immediately to the military authorities; the residue was sent to the chest of the Praetorian Prefect.85 These chests seem also to have paid the salaries of the provincial governors and their staffs.
The administration of the Imperial domains, which were extensive and were increased from time to time by the confiscation of the property of persons convicted of treason, demanded a separate department and a whole army of officials. At the head of this department was the Count of the Private Estates.86 The Private Estate (res privata) had originally been organised by Septimius Severus, who determined not to incorporate the large confiscated estates of his defeated rivals in the Patrimony but to have them separately administered.87 In the fourth century the Patrimony and the Private Estate were combined and placed under a minister of illustrious rank. His officials administered the domains and collected the rent from the colons. The greater part of the Imperial lands were treated as State property of which the income was used for public purposes. But certain domains were set aside to furnish the Emperor’s privy purse. Thus the domains in Cappadocia were withdrawn from the control of the Count of Private Estates and placed under the control of the Grand Chamberlain.88 And in the same way, in the west, certain estates in Africa (fundi domus divinae per Africam) were appropriated to the personal disposition of the Emperor, although they remained under the control of the Count.
What were the relations between the fisc or treasury of the Count of the Sacred Largess on one hand, and the chests of the Praetorian Prefects and the treasury of the Count of the Private Estates on the other? We may conjecture that the Prefects paid out of the treasuries directly the salaries of all the officials, both central and provincial, who were under their control; that in the same way the Count of the Private Estates paid out of the monies that came in from the domains all the officials who were employed in their administration; and that all that remained over, after the expenses of the departments had been defrayed, was handed over to the treasury of the Count of the Sacred Largess.89 This was the public treasury which had to supply the money required for all purposes with the four exceptions of the Emperor’s privy purse, the upkeep of the administration of the Imperial domains, the maintenance of the civil service under the Praetorian Prefects, and the payment of the army.
It has already been observed that no figures are recorded either for the annual revenue or for the annual expenditure. We have no data to enable us to conjecture, however roughly, the yield of the mines or of the rents of the Imperial domains. There is some material for forming a minimum estimate of the money value of the land-tax in Egypt, but even here there is much uncertainty.90 Turning to expenditure, we find that the evidence points to 500,000 or thereabouts as the lowest figure we can assume for the strength of the army in the time of Theodosius the Great. The soldiers were paid from the annona. When this payment in kind was commuted into coin, it was valued at 25 or 30 solidi a year for each soldier.91 The annual value of the annona must then have exceeded 12½ million solidi or nearly 8 million sterling. Of the salaries paid to the civil and military officials and their staffs we can only say that the total must have exceeded, and may have far exceeded, £400,000.92
From the general consideration that the population of the Empire at the lowest estimate must have been 50 millions, we might assume as the minimum figure for the revenue 50 million solidi, on the ground that in a state which was severely taxed the taxation could not have been less than 1 solidus per head.93 That would be about £31,250,000. It is probably much under the mark.
Of the financial problems with which Diocletian and Constantine had to deal, one of the most difficult was the medium of exchange. In the third century the Empire suffered from scarcity of gold. The yield of the mines had decreased; and a considerable quantity of the precious metals was withdrawn from circulation by private people, who during that troubled period buried their treasures. But the chief cause of the scarcity was the drain of gold to the east in exchange for the Oriental wares which the Romans required. In the first century A.D. the annual export of gold to the east is said to have amounted (at the least) to a million pounds sterling.94 The Emperors resorted to a depreciation of the coinage, and up to a certain point this perhaps was not particularly disadvantageous so far as internal trade was concerned, since the value of the metals had risen in consequence of the scarcity. When Diocletian came to the throne there was practically nothing in circulation but the double denarius, which ought to have been a silver coin equivalent to about 1s. 9d.), but was now made of copper, with only enough silver in it to give it a whitish appearance, and worth about a halfpenny. Both Aurelian and Diocletian made attempts to establish a stable monetary system,