Kujala Kadphises established the first Kushana kingdom after defeating five principalities. His son, Vima Kadphises continued his father’s aggressive policy and conquered northern India all the way down to Mathura or perhaps even up to Varanasi.
Kanishka was the greatest of all the rulers of Kushana. The Kushana Empire continued to rise during the reign of Kanishka. The vast extent of Kanishka’s empire probably stretched upto Varanasi in the east and from Kashmir in the north to the coast of Gujarat in the south.
Not much is known about his hold on Central Asia, but Kanishka wished to control the trade routes connecting India with Rome. Those land and sea routes which would enable this trade to bypass the Parthians’ routes. This trade must have been very profitable to the Kushanas. Gold became the most important medium of exchange for the Roman trade with India, and this must have greatly contributed to the rise of the Kushanas to prosperity and power. Kanishka achieved fame also as one of the Buddhist rulers of India. He built the great stupa at Peshawar.