Kavad I vs Kujula Kadphises

Kavad I embraced the Mazdakite movement, a religious and social reformist sect that advocated for communal property and egalitarianism. This support alienated the Zoroastrian clergy and nobility, leading to political instability.

The Sasanian nobility and Zoroastrian clergy, opposed to Kavad's Mazdakite policies, deposed him and imprisoned him in the 'Castle of Oblivion'. His brother Jamasp was placed on the throne as a puppet ruler.

Kavad escaped from prison with the help of his supporters and fled to the Hephthalite Huns. With their military backing, he returned to Persia, defeated Jamasp, and was restored as king, now indebted to the Hephthalites.

After his restoration, Kavad I implemented significant tax and administrative reforms to strengthen the central government. He introduced a fixed land tax and reorganized the bureaucracy, reducing the power of the nobility.

Kujula Kadphises united the five Yuezhi tribes of Bactria into a single confederation. This unification laid the foundation for the Kushan Empire, which would become a major power in Central Asia and India.

Kujula Kadphises issued the first Kushan coins, imitating Roman and Greek designs. These coins featured his portrait and the title 'Kushan' in Greek script, establishing a numismatic tradition for the empire.

Kujula Kadphises led Kushan forces to conquer the Kabul Valley from the Indo-Parthians. This expanded Kushan territory into the Indian subcontinent and established control over key trade routes.