Within Buddhist mythology, Sadashkana (Kharosthi: 𐨮𐨿𐨐𐨞𐨆‎𐨯𐨡 ', ' ) according to the gold plate inscription of Senavarman, mentions Sadashkana as the Devaputra (son of god), son of maharaja rayatiraya Kujula Kataphsa (Kujula Kadphises): He was the son of the founder of Kushan empire and his brother was Sadaṣkaṇa, their next generation was Kanishka. The Chinese Book of Later Han 後漢書 chronicles gives an account of the formation of the Kushan empire based on a report made by the Chinese general Ban Yong to the Chinese Emperor c. 125 AD: "More than a hundred years later [than the conquest of Bactria by the Da Yuezhi], the prince [xihou] of Guishuang (Badakhshan) established himself as king, and his dynasty was called that of the Guishuang (Kushan) King. He invaded Anxi (Indo-Parthia), and took the Gaofu (Kabul) region. He also defeated the whole of the kingdoms of Puda (Paktiya) and Jibin (Kapisha and Gandhara). Qiujiuque (Kujula Kadphises) was more than eighty years old when he died. His son, Yangaozhen [probably Vema Tahk (tu) or, possibly, his brother Sadaṣkaṇa ], became king in his place. He defeated Tianzhu [North-western India] and installed Generals to supervise and lead it. The Yuezhi then became extremely rich. All the kingdoms call [their king] the Guishuang [Kushan] king, but the Han call them by their original name, Da Yuezhi."

• Book of Later Han. The Kushans were one of five branches of the Yuezhi confederation, a possibly Iranian or Tocharian, Indo-European nomadic people who migrated from Gansu and settled in ancient Bactria. Ban Gu's Book of Han tells us the Kushans (Kuei-shuang) divided up Bactria in 128 BC. Fan Ye's Book of Later Han "relates how the chief of the Kushans, Ch'iu-shiu-ch'ueh (the Kujula Kadphises of coins), founded by means of the submission of the other Yueh-chih clans the Kushan Empire, known to the Greeks and Romans under the name of Empire of the Indo-Scythians."

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