Indo-Sassanids

The Kushano-Sassanids or Kushanshas (mistakenly called Indo-Sassanians) were a branch of the Sassanid Persians who established their rule in the northwestern Pakistan during the third and fourth centuries at the expense of the declining Kushans. They were in turn displaced in 410 by the invasions of the Huna people. They were able to re-establish some authority after the Sassanids destroyed the Hephthalites in 565, but their rule collapsed under Arab attacks in the mid 7th century.

The Sassanids, shortly after victory over the Parthians, extended their dominion into Bactria during the reign of Ardashir I around 230 CE, then further to the eastern parts of their empire in western Pakistan during the reign of his son Shapur I (240–270). Thus the Kushans lost their western territory (including Bactria and Gandhara) to the rule of Sassanid nobles named Kushanshahs or "Kings of the Kushans".

Around 325, Shapur II was directly in charge of the southern part of the territory, while in the north the Kushanshahs maintained their rule until the rise of the Kidarites.

The decline of the Kushans and their defeat by the Kushano-Sassanids led to the rise of the Hephthalites who conquered Bactria and Gandhara, thus replacing the Kushano-Sassanids, until the arrival of Islam to Pakistan.

The Hephthalites dominated the area until they were defeated in 565 AD by an alliance between the Gokturks and Sassanids, and some Indo-Sassanid authority was re-established. The Kushano-Hephthalites were able to set up rival states in Kapisa, Bamiyan, and Kabul. The 2nd Indo-Sassanid period ended with the collapse of Sassanids to the Rashidun Caliphate in the mid 7th century. Sind remained independent until the Arab invasions of India in the early 8th century. The Kushano-Hephthalites or Turkshahis were replaced by the Shahi in the mid 8th century.

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