From Maximian, God, the avenger of religion and of His people, turned his eyes to Galerius, the author of the accursed persecution, that in his punishment also He might manifest the power of His majesty. Galerius, too, was purposing to celebrate his twentieth anniversary; and as, under that pretext, he had, by new taxes payable in gold and silver, oppressed the provinces, so now, that he might recompense them by celebrating the promised festival, he used the like pretext for repeating his oppressions.
Who can relate in fit terms the methods used to harass mankind in levying the tax, and especially with regard to grain and the other fruits of the earth? The officers, or rather the executioners, of all the different magistrates, seized on each individual, and would never let go their hold. No man knew to whom he ought to make payment first. There was no dispensation given to those who had nothing; and they were required, under pain of being variously tortured, instantly to pay, notwithstanding their inability.
Many guards were set round, no breathing time was granted, or, at any season of the year, the least respite from exactions. Different magistrates, or the officers of different magistrates, frequently contended for the right of levying the tax from the same persons. No threshing-floor without a tax-gatherer, no vintage without a watch, and nought left for the sustenance of the husbandman! That food should be snatched from the mouths of those who had earned it by toil, was grievous: the hope, however, of being afterwards relieved, might have made that grievance supportable; but it was necessary for every one who appeared at the anniversary festival to provide robes of various kinds, and gold and silver besides.
And one might have said, “How shall I furnish myself with those things, O tyrant void of understanding, if you carry off the whole fruits of my ground, and violently seize its expected produce?” Thus, throughout the dominions of Galerius, men were spoiled of their goods, and all was raked together into the imperial treasury, that the emperor might be enabled to perform his vow of celebrating a festival which he was doomed never to celebrate.
Source: Of the Manner In Which the Persecutors Died (New Advent)