Though the Parthians had, so far as we can tell, no native literature, yet writing was familiar to them, and was widely used in matters of business. Not only were negotiations carried on with foreign powers by means of despatches, but the affairs of the empire generally were conducted by writing. A custom-house system was established along the frontier, and all commodities liable to duty that entered the country were registered in a book at the time of entry by the custom-house officer. In the great cities where the Court passed a portion of the year, account was kept of the arrival of strangers, whose names and descriptions were placed upon record by the keepers of the gates. The orders of the Crown were signified in writing to the satraps; and they doubtless corresponded with the Court in the same way. In the earlier times the writing material commonly used was linen; but shortly before the time of Pliny, the Parthians began to make paper from the papyrus, which grew in the neighborhood of Babylon, though they still employed in preference the old material.
There was a considerable trade between Parthia and Rome, carried on by means of a class of merchants. Parthia imported from Rome various metals, and numerous manufactured articles of a high class. Her principal exports were textile fabrics and spices. The textile fabrics seem to have been produced chiefly in Babylonia, and to have consisted of silks, carpets, and coverlets. The silks were largely used by the Roman ladies. The coverlets, which were patterned with various colors, fetched enormous prices, and were regarded as fit adornments of the Imperial palace. Among the spices exported, the most celebrated wore bdellium, and the juncus odoratus or odoriferous bulrush.
The Parthians had many liberal usages which imply a fairly advanced civilization. Their tolerance of varieties in religion has been already mentioned. Even in political matters they seem to have been free from the narrowness which generally characterizes barbarous nations. They behaved well to prisoners, admitted foreigners freely to offices of high trust, gave an asylum to refugees, and treated them with respect and kindness, were scrupulous observers of their pledged word, and eminently faithful to their treaty obligations. On the other hand, it must be admitted that they had some customs which indicate a tinge of barbarism. They used torture for the extraction of answers from reluctant persons, employed the scourge to punish trifling offences, and, in certain cases, condescended to mutilate the bodies of their dead enemies. Their addiction to intemperance is also a barbaric trait. They were, no doubt, on the whole, less civilized than either the Greeks or Romans; but the difference does not seem to have been so great as represented by the classical writers.
Speaking broadly, the position that they occupied was somewhat similar to that which the Turks hold in the system of modern Europe. They had a military strength which caused them to be feared and respected, a vigor of administration which was felt to imply many sterling qualities. A certain coarseness and rudeness attached to them which they found it impossible to shake off; and this drawback was exaggerated by their rivals into an indication of irreclaimable barbarity. Except in respect of their military prowess, it may be doubtful if justice is done them by any classical writer. They were not merely the sole rival which dared to stand up against Rome in the interval between B.C. 65 and A.D. 226, but they were a rival falling in many respects very little below the great power whose glories have thrown them so much into the shade. They maintained from first to last a freedom unknown to later Rome; they excelled the Romans in toleration and in liberal treatment of foreigners, they equalled them in manufactures and in material prosperity, and they fell but little short of them in the extent and productiveness of their dominions. They were the second power in the world for nearly three centuries, and formed a counterpoise to Rome which greatly checked Roman decline, and, by forcing the Empire to exert itself, prevented stagnation and corruption.
It must, however, be confessed, that the tendency of the Parthians was to degenerate. Although the final blow was struck in an unexpected quarter, and perhaps surprised the victors as much as the vanquished, still it is apparent that for a considerable space before the revolt of Artaxerxes the Parthian Empire had shown signs of failing strength, and had tended rapidly towards decay and ruin. The constant quarrels among the Arsacidae and the incipient disintegration of the Empire have been noticed. It may be added here that a growing barbarism, a decline in art and letters, is observable in the Parthian remains, such as have usually been found to accompany the decrepitude of a nation. The coinage has from first to last a somewhat rude character, which indicates that it is native, and not the production of Greek artists. But on the earlier coins the type, though not indicative of high art, is respectable, and the legends are, with few exceptions, perfectly correct and classical. Barbarism first creeps in about the reign of Gotarzes, A.D. 42-51. It increases as time goes on, until, from about A.D. 133, the Greek legend upon the coins becomes indistinct and finally unintelligible, the letters being strewn about the surface of the coin, like dead soldiers over a field of battle. It is, clear that the later directors of the mint were completely ignorant of Greek, and merely attempted to reproduce on the coin some semblance of a language which neither they nor their countrymen understood. Such a condition of a coinage is almost without parallel, and indicates a want of truth and honesty in the conduct of affairs which implies deep-seated corruption. The Parthians must have lost the knowledge of Greek about A.D. 130, yet still a pretence of using the language was kept up. On the tetra-drachms—comparatively rare coins—no important mistake was committed; but on the more usual drachm, from the time of Gotarzes, the most absurd errors were introduced, and thenceforth perpetuated. The old inscription was, in a certain sense, imitated, but every word of it ceased to be legible: the old figures disappeared in an indistinct haze, and—if we except the head and name of the king (written now in a Semitic character)—the whole emblazonment of the coin became unmeaning. A degeneracy less marked, but still sufficiently clear to the numismatic critic, is observable in the heads of the kings, which, in the earlier times, if a little coarse, are striking and characteristic; while in the later they sink to a conventional type, rudely and poorly rendered, and so uniform that the power of distinguishing one sovereign from another rests no longer upon feature, but upon mere differences in the arrangement of hair, or beard, or head-dress.