The Arab Conquests in Central Asia

CITED

PREFACE

THE first draft of this work was presented to the University of London in December 1921, under the title of The Arab Conquest of Transoxania, as a thesis for the degree of Master of Arts, and was approved by the Senate in January 1922, for publication as such. During the year my attention was taken up in other directions and, except for the publication of two studies on the subject in the Bulletin of the School of Oriental Studies, nothing further was done until by the generosity of the Trustees of the Forlong Bequest Fund an opportunity of publication was offered. In its present form the work has been largely rewritten and revised. It makes no claim to present a complete historical account of the Arabs in Central Asia, but is intended solely as a critical study of the authorities in greater detail than has hitherto been made. Much is therefore omitted because it has already been dealt with in the standard histories. In order to keep down the cost of publication, the extensive references which originally accompanied the text have been cut down to a few notes at the end of each chapter. No references are given when, as in the great majority of cases, the authority for the statements made can easily be found in the appropriate place either in Tabarī or Balādhurī.

I regret that several works which are indispensable for a thorough study of the subject have, for linguistic reasons, been inaccessible to me. Such are van Vloten’s Opkomst der Abbasiden, and almost the whole range of Russian research work. Through the kindness of Sir Denison Ross, however, I have been able to avail myself of a draft MS. translation of the most important and valuable of them all, Professor W. Barthold’s Turkestan, as well as of his as yet unpublished London lectures on The Nomads of Central Asia. My sincere thanks are due to Sir Denison Ross also for his continued interest and material assistance ever since he first introduced me to the subject; to Sir Thomas Arnold for much encouragement and helpful counsel; to Professor Barthold, who has read the MS. through and made a number of valuable suggestions; to the Trustees of the Forlong Bequest Fund for their kindness in undertaking the publication; and in no small measure to my wife, who has given much time and labour to preparing the MS. for publication.

London,

April, 1923.

I. INTRODUCTION

THE OXUS BASIN

Early History.

The Oxus is a boundary of tradition rather than of history. Lying midway between the old frontier of Aryan civilisation formed by the Jaxartes and the Pamir and the natural strategic frontier offered by the northeastern escarpment of the plateau of Īrān, it has never proved a barrier to imperial armies from either side. It was not on the Oxus but on the Jaxartes that Alexander’s strategic insight fixed the position of Alexander Eschate, and when the outposts of Persian dominion were thrust back by the constant pressure of the Central Asian hordes, their retreat was stayed not on the Oxus but on the Murghāb. Thus when the tide of conquest turned and the Arabs won back her ancient heritage for Persia, they, like Alexander, were compelled to carry their arms ever further to the East and all unknowing re-establish the frontiers of the Achaemenid Empire. It was from the legends of Sāsānian times, enshrined in the pages of the historians and the national epic of Firdawsī, that the Oxus came to be regarded as the boundary between Īrān and Tūrān.

Through all the centuries of invasion, however, the peoples of Sogdiana and the Oxus basin remained Iranian at bottom, preserving an Iranian speech and Iranian institutions. But the political conditions of the country at the period of the Arab conquests were so complex that it is necessary to trace briefly the course of their development.

The second century B.C. was a period of upheaval in Central Asia: the powerful Hiung-Nu peoples were dispossessing weaker tribes of their pasture lands and forcing them to migrate westwards. Between 150 and 125 B.C. a succession of nomadic tribes, the last and most powerful of which were a branch of the Yueh-Chi, were driven down into Sogdiana. It is now generally held that these tribes were of Aryan origin, though the question is not perhaps settled with absolute certainty. Before long, however, a second group, the K’ang, possessed themselves of Sogdiana, driving the Yueh Chi on into Bactria and the Afghan mountains (1). In these districts they found, alongside the Iranian peasantry, a settled population of Tukhari (in Chinese, Ta-Hia), already noted in the Chinese annals for their commercial enterprise (2), and while at first the nomad tribes introduced complete confusion, it would seem that they rapidly absorbed, or were absorbed by, the native elements, and thus assimilated the Hellenistic civilisation of Bactria. From this fusion arose, about 50 A.D., the powerful Kushan Empire which spread into India on the one side and probably maintained some form of suzerainty over the K’ang kindgoms of Sogdiana on the other. Under the new empire, Buddhism was acclimatised in Turkestan, and Sogdiana developed into a great entrepôt for Chinese trade with the West. Towards the close of the third century the Kushan Empire, weakened by attacks from the new national dynasties in India and Persia, reverted to its primitive form of small independent principalities, which, however, retained sufficient cohesion to prevent a Persian reconquest. It is practically certain that Sāsānian authority never extended beyond Balkh and rarely as far. In the fourth and fifth centuries references are made to a fresh horde of nomads in the north-east, the Juan-Juan (Chionitae, Avars) (3), but it does not appear that any new settlements were made in the Oxus countries.

In the middle of the fifth century, another people, the Ephthalites (Arabic Haytal, Chinese Ye-Tha), perhaps a branch of the Hiung-nu, not only completely overran the former Kushan territories, but by successive defeats of the Persian armies forced the Sāsānid Kings to pay tribute. The Ephthalites appear to have been a nomadic people organised as a military caste of the familiar Turkish type, and the existing institutions and principalities, in large part at least, continued side by side with them (4). Their rule was too transitory to produce any lasting effects, or to inflict any serious injury on the commerce and prosperity of Sogdiana.

The rise of the Central Asian empire of the Turks proper (Tu-Kueh) dates from their overthrow of the Juan-Juan in Mongolia in 552, under their great Khan, Mokan. His brother Istämi (the Silzibul of the Byzantine historians), the semi-independent jabghu of the ten tribes of Western Turks, after consolidating his power in the Ili and Chu valleys, formed an alliance with Khusrū Anūshīrwān, and in a joint attack between 563 and 568 the two powers completely overthrew the Ephthalite kingdom and divided their territories. For a brief moment the Oxus was the actual boundary between Īrān and Tūrān; under pressure from the silk traders of Sogdiana, however, the alliance was broken and the weaker successors of Anūshīrwān could scarcely do more than maintain their outpost garrisons on the Murghāb. From this time the Ephthalites, like the Kushans, were gradually assimilating to the Iranian population (5), though the change was less rapid in the Cisoxine lands of Lower Tukhāristān, Bādghīs, and Herāt, where Ephthalite principalities were re-constituted, probably with Turkish support, and continued to give Persia much trouble on her north-eastern frontiers (6). On the other hand the Turks of the five western tribes (Nu-she-pi), who became independent after the break up of the Great Khanate about 582, maintained their suzerainty over Sogdiana and the middle Oxus basin by frequent expeditions, in one case at least as far as Balkh. There is no trace in our records of extensive Turkish immigration into the conquered lands; at most, small groups of Turks wandered south with their herds, especially, it would seem, south of the Iron Gate (7). In general, Turkish interference in the administration of the subject principalities was at first limited to the appointment of military governors and the collection of tribute. Thus, in the semi-legendary account given by An-Naysābūrī of the Turkish conquest of Bukhārā the Bukhār Khudāh is represented as the chief dihqān under the Turkish governor. It is possible also that the native princes maintained guards of Turkish mercenaries.

At this period, therefore, so far from the Oxus being a barrier, there was considerable intercommunication between the peoples on either side, and at least the elements of a racial and cultural unity, in spite of political divisions. This is a factor of importance in the history of the Arab conquests: the conquest of Transoxania is intimately linked with the fortunes of Lower Tukhāristān, and only became possible when the latter country was completely subdued. On the other hand, the Jaxartes formed a natural racial and political frontier. "Shāsh and Sughd have seldom run together" says Vambery, and in spite of nominal annexations on more than one occasion Muslim rule was not effectively imposed on Shāsh and Farghāna until some time after the final conquest of Transoxania. Their chief importance for the history of Transoxania is that they formed the jumping-off place for counter-invasions from the East. It is not without significance that of the two battles which were decisive in establishing Arab rule in Sogdiana one was fought to the west of Balkh and the other on the Talas river, far into the Turkish lands beyond the Jaxartes (see pp. 84 and 96).

Political Divisions.

Researches into Chinese records have now made it possible to obtain a more definite idea of the political conditions of these frontier provinces in the seventh century. All the principalities acknowledged the Khan of the Western Turks as overlord and paid tribute to him under compulsion; though, as will appear, there is good cause for doubting whether a Turkish army ever came in response to their appeals for support until the rise of the Türgesh power in 716.

Geographically the cultivated lands to the west and south-west of the middle Jaxartes are divided by the Hissar mountains into two well-defined areas. The northern area includes the rich valley of the Zarafshān and the lesser streams which descend the