Hindu-Kush in the context of "Hephthalite"

The Hephthalites (Bactrian: ηβοδαλο, romanized: Ebodalo), sometimes called the White Huns (also known as the White Hunas, in Iranian as the Spet Xyon and in Sanskrit and Prakrit as the Sveta-huna), were a people who lived in Central Asia during the 5th to 8th centuries CE, part of the larger group of Eastern Iranian Huns. They formed an empire, the Imperial Hephthalites, and were militarily important from 450 CE, when they defeated the Kidarites, to 560 CE, when combined forces from the First Turkic Khaganate and the Sasanian Empire defeated them. After 560 CE, they established "principalities" in the area of Tokharistan, under the suzerainty of the Western Turks (in the areas north of the Oxus) and of the Sasanian Empire (in the areas south of the Oxus), before the Tokhara Yabghus took over in 625.

The Imperial Hephthalites, based in Bactria, expanded eastwards to the Tarim Basin, westwards to Sogdia and southwards through Afghanistan, but they never went beyond the Hindu-Kush, which was occupied by the Alchon Huns, previously thought to be an extension of the Hephthalites. They were a tribal confederation and included both nomadic and settled urban communities. They formed part of the four major states known collectively as Xyon (Xionites) or Huna, being preceded by the Kidarites and by the Alkhon, and succeeded by the Nezak Huns and by the First Turkic Khaganate. All of these Hunnic peoples have often been controversially linked to the Huns who invaded Eastern Europe during the same period, and/or have been referred to as "Huns", but scholars have reached no consensus about any such connection.

The Turk Shahis were a dynasty of Western Turk, or mixed Turco-Hephthalite origin, that ruled from Kabul and Kapisa to Gandhara in the 7th to 9th centuries AD. They may have been of Khalaj ethnicity. The Gandhara territory may have been bordering the Kashmir kingdom to the east. From the 560s, the Western Turks had gradually expanded southeasterward from Transoxonia, and occupied Bactria and the Hindu Kush region, forming largely independent polities. The Turk Shahis may have been a political extension of the neighbouring Western Turk Yabghus of Tokharistan. In the Hindu Kush region, they replaced the Nezak Huns – the last dynasty of Bactrian rulers with origins among the Xwn (Xionite) and/or Huna peoples (who are sometimes also referred to as "Huns" who invaded Eastern Europe during a similar period).

The Turk Shahis arose at a time when the Sasanian Empire had already been conquered by the Rashidun Caliphate. The Turk Shahis then resisted for more than 250 years the eastward expansion of the Abbasid Caliphate, until they fell to the Persian Saffarids in the 9th century AD. The Ghaznavids then finally broke through into India after overpowering the declining subsequent Hindu Shahis and Gurjaras.

The Yavana Era, or Yona (Prakrit: Yoṇaṇa vaṣaye) was a computational era used in the Indian subcontinent from the 2nd century BCE for several centuries thereafter, probably starting in 174 BCE. It was initially thought that the era started around 180-170 BCE, and corresponded to accession to the Greco-Bactrian throne of Eucratides, who solidified Hellenic presence in the Northern regions of India. The Greeks in India flourished under the reign of the illustrious, Menander - greatest of the Yavana rulers, who campaigned as far as Pataliputra in Eastern India. It is now equated with the formerly theorized "Old Śaka era".

Harry Falk and others have suggested that the Yavana era actually started in 174 BCE, based on a reevaluation of the Azes era which is now thought to have started in 47/46 BCE. The exact historical event corresponding to the creation of this Yavana era is uncertain, but it may mark the alliance of Antimachos I and Apollodotus I in toppling Agathokles, thereby creating a unified realm north and south of the Hindu-Kush.