From the time that the Irano-Aryan ancestors had arrived in Russian Turkestan in anticipation of their descent into the hills of northwestern India, much of this grassy plain had been the home of those Iranians who remained behind while their kinsmen climbed the mountains which would take them into India and the Irano-Afghan plateau. These Iranians apparently developed, or borrowed, a high degree of adaptation to their steppe environment, and especially through the perfection of pastoral nomadism with the horse as chief instrument of mobility. They expanded through the passes to the eastward, which took them to Kashgaria, and there came in contact with the Chinese Empire. On the other side, they expanded westward into Europe, where we have already studied them in the form of Scythians and Sarmatians.
To the northwest of the vast Iranian domain, in Mongolia, a number of semi-agricultural, semi-pastoral tribes, possessing the sheep, probably also cattle, and perhaps wagons, but apparently not the horse, came in early times to the attention of the Chinese historians. By 800 B.C. we hear of a people called the Hiung-Nu, who gradually grew in importance until they came to dominate all of Mongolia.8 At a fairly late date, set by McGovern between 541 and 300 B.C., the Hiung-Nu presumably obtained horses, and learned to ride them. They seem to have acquired these animals from the Iranians or from Turkish-speaking peoples, along with the whole complex of horse nomadism. Chinese accounts of the Hiung-Nu later than the third century B.C. refer to them as typical plainsmen, strikingly similar in many cultural respects to the Scythians.
The six centuries, more or less, from 400 B.C. to 200 A.D., formed the period of greatness of the Hiung-Nu in Mongolia, during which they constantly harried China, and took possession of Chinese Turkestan. Despite their conquest, however, Iranian languages, and the mysterious Tokharian B, persisted in the towns until 800 A.D. or later. At length the Chinese took measures to rid themselves of this nuisance, and succeeded in defeating the Hiung-Nu so completely that they abandoned their territory and disappeared to the westward.
The last mention of the Hiung-Nu in Chinese sources is about 170 AL. and, exactly two hundred years later, the Huns appeared on the banks of the Don in Russia. McGovern has presented a convincing argument to prove that the two were the same people; that their passage across Asia took them across a space sterile of historians, between the spheres of Chinese and of Byzantine chroniclers. Only one glow of light appears in this interim; in 290 A.D. Tigranes the Great of Armenia hired some such people as mercenaries.
The history of the Huns in Europe does not require elaborate treatment. Having defeated the Ostrogoths and sent them and their kinsmen scurrying westward, the Huns moved to the present Hungary, which they made their headquarters. From here they sent expeditions to Rome, to Germany, and to France, where Attila was defeated in the battle of the Catalonian fields in 451 A.D. After his death two years later, the Runs retired to eastern Europe, and many of them united with their relatives the Bolgars, who had settled between the Ugrian and Finnic tribes of the middle Volga and Kama rivers, where, under Bolgar leadership, a great state arose, which flowered between the eighth and fourteenth centuries.
In the meantime, the Huns in central Asia raided Mesopotamia, Persia, Afghanistan, and India; presumably the Turkish penetration of central Siberia dates likewise from the period between 200 and 400 A.D. This span of two centuries marks the beginning of the great expansion...