Their power was not destined to endure for long. By the end of the third century A.D. they had lost most of their conquests in the south of Paropamisus, including Kashmir. They were finally expelled from Bactria itself by the Ephthalites, or White Huns, about the year A.D. 430.
The last Kushan king of whom we find a trace in history was named Kitolo. He conquered Gāndhāra, or Kandahār; but was forced to return to his own dominion by an irruption of White Huns. The son whom he left in charge of the new province established his capital at Peshāwar.[46] The name of the founder of the Little Yué-Chi, as they were afterwards called, survives in the title of Shah Kator, chief of Chitral.
The Ephthalites, or White Huns, who, as we have seen, in the year A.D. 430 became possessed of Bactria, were in all probability of the same stock as the Yué-Chi. They are known to history under a great variety of names, such as Naphthalites, Hayāthila, and Yetha. This last is the name by which they are known to the Chinese, who always most carefully distinguish between the Yetha and the Yué-Chi.[47] The Yetha were of Tartaric origin, and are described as having anciently lived to the north of the Great Wall, and to have advanced southwards about the first century of our era. They then came under the domination of the Juen-Juen,[48] but emerging from this, they ultimately became masters of an empire which extended to the borders of Persia, and comprised Kiphin, Kharashar, Kāshghar, and Khotan. The arrival of the Yetha in Transoxiana about the year 425 of our era was the result of those migrations of Tartar peoples which took place in Central Asia at the beginning of the fifth century. About 360 the Juen-Juen advancing westwards became masters of all Tartary.[49] One of their kings, Tulun by name, who reigned at the beginning of the fifth century, carried his conquest from Corea to the confines of Europe. It was owing to these conquests that the various Hunnish tribes, driven from their ancient habitats by these new invaders, swept into Transoxiana in 425 (_i.e._ the Ephthalites), and into Europe, under Attila, in 430. On the appearance of the White Huns in the Oxus districts that country had been for five centuries in the possession of the Yué-Chi, or Kushans, as we have seen above, and they occupied the land for upwards of 130 years (425 to 557), during which period they were in close contact with the Sāsānides of Persia. The Kushans did not, however, immediately disappear from Central Asia, for we find references after this date in Chinese authors to small Kushan principalities in the Upper Oxus and Farghāna.