Interesting facts about the Kushana empire

A few nomadic tribes of central Asia had traveled Westward. They reached and settled down in what is present day Afghanistan and north-west frontiers of the Indian subcontinent. A branch of this tribe was Ku ei Shuang. They had established control over Bacteria. The Kushanas established a vast empire. The main credit of laying the foundations of the Kushana empire rests with Kujula Kadphises. Kashmir and Kabul were under his control. He was succeeded by his son Vima Kadphises. Vima's reign extended over a vast area around the India valley. He was the first to introduce a gold currency in the Indian subcontinent. Kanishka I, the soon of Vima was the greatest of the Kushana emperors. He resigned for close to 23 years. The Shaka era began from this particular year. During his reign Kushana role had spread over the vast Gangetic plains. Modern day Pakistan almost entirely under Kushana rule. Kanishka's capital was Purushapura or modern day Peshawar. However the principal seat of Kushana power was Bacteria. After him, Vashiska and Huvishka had become emperors. There was a gradual decline of the Kushana rule. They had even lost their control over Bactria. We don't hear about the Kushana's after 230 A.D.