The Cambridge History of India, Vol. I: Ancient India v1.c31.111

v1.c31.111

It was from this country, too, and under the leadership of Çaka and Pahlava satraps that the Kushāṇa power was extended to Western India; and in this manner were laid the foundations of the kingdom of the Kshatrapas of Surāshṭra and Mälwā, the 'Western Satraps,' who are known in the later Indian literature and inscriptions as 'Çakas.' This kingdom lasted from about the beginning of the second century to the end of the fourth, when it was conquered by the Guptas. The dates which appear on the coins and inscriptions of its princes are all in the era which starts from the beginning of Kanishka's reign in 78 A.D. They range from the year 41 to the year 310 (119–388 A.D.) and form the most continuous and complete chronological series found on the monuments of ancient India. It was in consequence of its long use by the Çaka princes of Western India that the era became generally known in India as the Çaka era—a name which effectually disguises its origin, and one which has in no small degree perplexed modern scholars in their endeavours to unravel 'the secret of Kanishka.'