The revolt which now occupied for a time the attention of Mithridates was that of Hyrcania. The Hyrcanians were Arians in race; they were brave and high-spirited, and under the Persian monarchs had enjoyed some exceptional privileges which placed them above the great mass of the conquered nations. It was natural that they should dislike the yoke of a Turanian people; and it was wise of them to make their effort to obtain their freedom before Parthia grew into a power against which revolt would be utterly hopeless. Hyrcania might now expect to be joined by the Medes, and even the Mardi, who were Arians like themselves, and could not yet have forgotten the pleasures of independence. But though the effort does not seem to have been ill-timed, it was unsuccessful. No aid was given to the rebels, so far as we hear, by any of their neighbors. Mithridates’s prompt return nipped the insurrection in the bud; Hyrcania at once submitted, and became for centuries the obedient vassal of her powerful neighbor.
The conquest of Media had brought the Parthians into contact with the rich country of Susiana or Elymais; and it was not long before Mithridates, having crushed the Hyrcanian revolt, again advanced westward, and invaded this important province. Elymais appears to have a had a king of its own, who must either have been a vassal of the Seleucidse, or have acquired an independent position by revolt after the death of Epiphanes. In the war which followed between this monarch and Mithridates, the Elymseans proved wholly unsuccessful, and Mithridates rapidly overran the country and added it to his dominions. After this he appears to have received the submission of the Persians on the one hand and the Babylonians on the other, and to have rested on his laurels for some years, having extended the Parthian sway from the Hindoo Koosh to the Euphrates.
The chronological data which have come down to us for this period are too scanty to allow of any exact statement of the number of years occupied by Mithridates in effecting these conquests. All that can be said is that he appears to have commenced them about B.C. 163 and to have concluded them some time before B.C. 140, when he was in his turn attacked by the Syrians. Probably they had been all effected by the year B.C. 150; since there is reason to believe that about that time Mithridates found his power sufficiently established in the west to allow of his once more turning his attention eastward, and renewing his aggressions upon the Bactrian kingdom, which had passed from the rule of Eucratidas under that of his son and successor, Heliocles.
Heliocles, who was allowed by his father a quasi-royal position, obtained the full possession of the Bactrian throne by the crime of parricide. It is conjectured that he regarded with disapproval his father’s tame submission to Parthian ascendency, and desired the recovery of the provinces which Eucratidas had been content to cede for the sake of peace. We are told that he justified his crime on the ground that his father was a public enemy; which is best explained by supposing that he considered him the friend of Bactria’s great enemy, Parthia. If this be the true account of the circumstances under which he became king, his accession would have been a species of challenge to the Parthian monarch, whose ally he had assassinated. Mithridates accordingly marched against him with all speed, and, easily defeating his troops, took possession of the greater part of his dominion. Elated by this success, he is said to have pressed eastward, to have invaded India, and overrun the country as far as the river Hydaspes, but, if it be true that his arms penetrated so far, it is, at any rate, certain that he did not here effect any conquest. Greek monarchs of the Bactrian series continued masters of Oabul and Western India till about B.C. 126; no Parthian coins are found in this region; nor do the best authorities claim for Mithridates any dominion beyond the mountains which enclose on the west the valley of the Indus.
By his war with Heliocles the empire of Mithridates reached its greatest extension. It comprised now, besides Parthia Proper, Bactria, Aria, Drangiana, Arachosia, Margiana, Hyrcania, the country of the Mardi, Media Magna, Susiana, Persia and Babylonia. Very probably its limits were still wider. The power which possessed Parthia, Hyrcania, and Bactria, would rule almost of necessity over the whole tract between the Elburz range and the Oxus, if not even over the region between the Oxus and the Jaxartes; that which held the Caspian mountains and eastern Media could not fail to have influence over the tribes of the Iranic desert; while Assyria Proper would naturally follow the fortunes of Babylonia and Susiana. Still the extent of territory thus indicated rests only on conjecture. If we confine ourselves to what is known by positive evidence, we can only say that the Parthian Kingdom of this period contained, at least, twelve provinces above enumerated. It thus stretched from east to west a distance of fifteen hundred miles between the Suleiman mountains and the Euphrates, varying in width from three or four hundred miles—or even more—towards the west and east, to a narrow strip of less than a hundred miles toward the centre. It probably comprised an area of about 450,000 square miles; which is somewhat less than that of the modern Persia.
Unlike the modern Persia, however, the territory consisted almost entirely of productive regions. The excellent quality of the soil in Parthia Proper, Hyrcania, and Margiana, has been already noticed. Bactria, the next province to Margiana towards the east, was less uniformly fertile; but still it contained a considerable proportion of good land along the course of the Oxus and its tributaries, which was cultivated in vineyards and cornfields, or else pastured large herds of cattle. The Mardian mountain territory was well wooded; and the plain between the mountains and the Caspian was rich in the extreme. Media, where it adjoined on the desert, was comparatively sterile; but still even here an elaborate system of artificial irrigation brought a belt of land under culture. Further west, in the Zagros chain, Media comprised some excellent pasture lands, together with numerous valleys as productive as any in Asia. Elymais was, in part, of the same character with the mountainous portion of Media, while beyond the mountain it sank down into a rich alluvium, not much inferior to the Babylonian. Babylonia itself was confessedly the most fertile country in Asia. It produced wheat, barley, millet, sesame, vetches, dates, and fruits of all kinds. The return of the wheat crop was from fifty to a hundred-and-fifty-fold; while that of the barley crop was three hundred-fold. The dates were of unusual size and superior flavor; and the palm, which abounded throughout the region, furnished an inexhaustible supply both of fruit and timber.
The great increase of power which Mithridates had obtained by his conquests could not be a matter of indifference to the Syrian monarchs. Their domestic troubles—the contentions between Philip and Lysias, between Lysias and Demetrius Soter, Soter and Alexander Balas, Balas and Demetrius II., Demetrius II. and Tryphon, had so engrossed them for the space of twenty years (from B.C. 162 to B.C. 142) that they had felt it impossible, or hopeless, to attempt any expedition towards the East, for the protection or recovery of their provinces. Mithridates had been allowed to pursue his career of conquest unopposed, so far as the Syrians were concerned, and to establish his sway from the Hindoo Koosh to the Euphrates. But a time at last came when home dangers were less pressing, and a prospect of engaging the terrible Parthians with success seemed to present itself. The second Demetrius had not, indeed, wholly overcome his domestic enemy, Tryphon; but he had so far brought him into difficulties as to believe that he might safely be left to be dealt with by his wife, Cleopatra, and by his captains. At the same time the condition of affairs in the East seemed to invite his interference, Mithridates ruled his new conquests with some strictness, suspecting, probably, their fidelity, and determined that he would not by any remissness allow them to escape from his grasp. The native inhabitants could scarcely be much attached to the Syro-Macedonians, who had certainly not treated them very tenderly; but a possession of 170 years’ duration confers prestige in the East, and a strange yoke may have galled more than one to whose pressure they had become accustomed. Moreover, all the provinces which Parthia took from Syria contained Greek towns, and their inhabitants might at all times be depended on to side with their countrymen against the Asiatics. At the present conjuncture, too, the number of the malcontents was swelled by the addition of the recently subdued Bactrians, who hated the Parthian yoke, and longed earnestly for a chance of recovering their freedom. Thus when Demetrius II., anxious to escape the reproach of inertness, determined to make an expedition against the great Parthian monarch, he found himself welcomed as a deliverer by a considerable number of his enemy’s subjects, whom the harshness, or the novelty, of the Parthian rule had offended. The malcontents joined his standard as he advanced; and supported, as he thus was, by Persian, Elymsen, and Bactrian contingents, he engaged and defeated the Parthians in several battles. Upon this, Mithridates, finding himself inferior in strength, had recourse to stratagem, and having put Demetrius off his guard by proposals of peace, attacked him, defeated him, and took him prisoner. The invading army appears to have been destroyed. The captive monarch was, in the first instance, conveyed about to the several nations which had revolted, and paraded before each in turn, as a proof to them of their folly in lending him aid, but afterwards he was treated in a manner befitting his rank and the high character of his captor. Assigned a residence in Hyrcania, he was maintained in princely state, and was even promised by Mithridates the hand of his daughter, Ehodo-guns. The Parthian monarch, it is probable, had the design of conquering Syria, and thought it possible that he might find it of advantage to have a Syrian prince in his camp, well disposed towards him, connected by marriage, and thus fitted for the position of tributary monarch. But the schemes of Mithridates proved abortive. His career had now reached its close. Attacked by illness not very long after his capture of Demetrius, his strength proved insufficient to bear up against the malady, and he died after a glorious reign of about thirty-eight years, B.C. 136.
CHAPTER VI.
System of government established by Mithridates I. Constitution of the Parthians. Government of the Provinces. Laws and Institutions. Character of Mithridates I.