In the post-Mauryan era Central Asia and north-western India witnessed hectic and shifting political scenes. The Great Yuehi-Chi driven out of fertile land in western China migrated towards the Aral Sea. There they encountered the Sakas and overthrew them. They settled in the valley of Oxus and with the occupation of the Bactrian lands the great hordes were divided into five principalities.A century later the Kushan section attained predominance over the others. Their leader was Kadphises. Thus began the history of Kushans. Kadphises attacked the regions south of Hindu Kush, conquered Kabul and annexed Gandhara including the kingdom of Taxila. He died in 78 AD. By then the Kushans had supplanted the princes belonging to the Indo-Greeks Saka and Indo-Parthian communities along the frontiers of India. The successor of Kadphises was Vima Kadphsis. He conquered large parts of North India. His coins show that his authority extended as far as Benaras and as well as Indus basin. His power extended as far as Narmada and Saka Satraps in Malwa and Western India acknowledged his sovereignty.
The next ruler Kanishka belonged to the little Yuehi-Chi section of the horde. His capital was Purusyapura and here he built many Buddhist buildings. In his early days he annexed Kashmir and consolidated his rule in the Indus and the Gangetic basin. His army crossed the pamirs and inflicted a defeat on the Chinese. A large number of inscriptions were incised during the time of Kanishka and his successor. He became an active patron of Buddhist Church during the later part of the reign. His coins prove that he honoured a medley of Gods -Zoroastrian, Greek, Mitraic and Indian. The prominent Indian deity was God Shiva. He also convened a council of Buddhist theologians to settle disputes relating to Buddhist faith and practices.