The mountain passes in northwestern Pakistan, most notably the Khyber Pass, are the routes taken by peoples who migrate to India.

Although unrecorded migrations may have taken place earlier, it is certain that migrations increased in the second millennium BCE.

The records of these Indo-European speakers are literary, not archaeological: the earliest evidence of the group is from Vedic Sanskrit, the language used in the ancient preserved texts of the Indian subcontinent, the foundational canon of Hinduism known as the Vedas, collections of orally transmitted hymns.

The speakers of Old Indo-Aryan appear in the greatest of these hymns, the Rig Veda, as a tribally organized, pastoral, and pantheistic people.

The Indo-Aryan superstrate in Mitanni, which suggests that an Indo-Aryan elite imposed itself over the Hurrian population in the course of the Indo-Aryan expansion, is of similar age as the Rigveda (and almost identical to it), but the only evidence is a number of loanwords.

The emergence of the Gandhara grave culture in the Swat Valley in about 1600 BCE represents a major cultural change, which, with its introduction of new ceramics, new burial rites, and the horse, is a major candidate for early Indo-Aryan presence.

The two new burial rites—flexed inhumation in a pit and cremation burial in an urn—are, according to early Vedic literature, both practiced in early Indo-Aryan society.

Horse-trappings indicate the importance of the horse to the economy of the Gandharan grave culture.

Two horse burials indicate the importance of the horse in other respects.

Horse burial is a custom that Gandharan grave culture has in common with Andronovo, though not within the distinctive timber-frame graves of the steppe.

A number of small princely states rise and fall in North India in the sixth century BCE.

The semi-independent kingdom of Gandhara, roughly located in northern Pakistan and centered in the region of Peshawar, stands between the expanding kingdoms of the Ganges Valley to the east and the Achaemenid Empire of Persia to the west.

Gandhara probably comes under the influence of Persia during the reign of Cyrus the Great, who reigns from 559 to 530 BCE.

…into the country of the Paropamisadae, where Alexander founds Alexandria by the Caucasus at an important junction of communications in the Hindu Kush.

The Ta Yüeh-chih had earlier moved into territory in the northern part of present-day Afghanistan and had taken control of Bactria.

Kujula Kadphises, the Yüeh-chih chief, conquers northern India in the first century CE.

He is succeeded by his son Vima, after whom comes Kaniska, the most powerful among the Kusana, or Kushan, kings, as the dynasty comes to be called.

A title of Central Asian derivation is the daivaputra of the Kusanas, which is believed to have come originally from the Chinese “son of heaven”, emphasizing the divinity of kingship.

The date of Kaniska's accession is controversial, ranging from 78 to 248.

The generally accepted date of 78 is also the basis for an era presumably started by the Sakas and used in addition to the Gregorian calendar by the present Indian government; the era, possibly commemorating Kaniska's accession, is widely used in Malava, Ujjain, Nepal, and Central Asia.

Kaniska's ambitions include control of Central Asia, which, if not directly under the Kusanas, did come under their influence.

The Kusana kingdom is essentially oriented to the north, controlling territory up to the Pamirs in the north and Bukhara in the west, although it extends southward as far as Saci and into the Ganges Valley as far as Varanasi.

The Kusanas, who were at the center of the silk trade between China and the west, establish their capital at Purusapura (near modern Peshawar).

Under Kaniska, the Kusanas, who are Buddhist, built thousands of monasteries and stupas.

Gandhara soon becomes both a place of trade and of religious study and pilgrimage.

Traces remain of the presence of the Kushans in the area of Bactria.

Archaeological structures are known in Takht-I-Sangin, and Surkh Kotal (a monumental temple).

The earliest documented ruler, and the first one to proclaim himself as a Kushan ruler, s Heraios.

He calls himself a "tyrant" on his coins, and also exhibits skull deformation.

He may have been an ally of the Greeks, and he shared the same style of coinage.

Heraios may have been the father of the first Kushan emperor Kujula Kadphises.

Gandhara falls to the Kushans in 48.

The conquest of northwest India led by Kujula Kadphises lays the basis for the Kushan Empire which will be rapidly expanded by his descendants.

The origins of Kujula Kadphises are obscure, and it is usually considered he was a descendant of the Kushan ruler Heraios, or even identical with him.

Interestingly however, Kujula shares his name (on some of his "Hermaeus" coins, or on his "Augustus" coins) with some of the last Indo-Scythian rulers, such as Liaka Kusulaka, or his son Patika Kusulaka, which might suggest some family connection.

In the process of their expansion eastward, Kujula Kadphises and his son Vima Takto seem to have displaced the Indo-Parthian kingdom, established in northwestern India by the Parthian Gondophares since around CE 20.

This invasion of Kujula Kadphises is thought to have occurred during the reign of Abdagases and Sases, the successors of Gondophares, after 45 CE.

Most of Kujula's coins are Hellenic or Roman in inspiration.

Some coins use the portrait, name and title of the Indo-Greek king Hermaeus on the obverse, indicating Kujula's wish to relate himself to the Indo-Greek king.

Since the Kushans and their predecessors the Yuezhi were conversant with the Greek language and Greek coinage, the adoption of Hermaeus cannot have been accidental: it either expresses a filiation of Kujula Kadphises to Hermaeus by alliance (possibly through Sapadbizes or Heraios), or simply a wish to show himself as heir to the Indo-Greek tradition and prestige, possibly to accommodate Greek populations.

These coins bear the name of Kujula Kadphises with representations of the Greek demi-god Heracles on the back, and titles ("Yavugasa") presenting Kujula as a "ruler" (not actual king), and a probable Buddhist ("Dharmathidasa", follower of the Dharma).

Later coins, possibly posthumous, do describe Kujula as "Maharajasa", or "Great King.

Some fewer coins of Kujula Kadphises also adopted a Roman style, with effigies closely resembling Caesar Augustus, although all the legends were then associated with Kujula himself.

Such influences are linked to exchanges with the Roman Empire around that date.

The Kushans had earlier moved into territory in the northern part of present-day Afghanistan and had taken control of Bactria.

Kanishka, the greatest of the Kushan rulers (r. ca. CE 120-60), extends his empire from Patna in the east to Bukhara in the west and from the Pamirs in the north to central India, with the capital at Peshawar (at this time Purushapura).

Kushan territories will eventually be overrun by the Huns in the north and taken over by the Guptas in the east and the Sassanians of Persia in the west.

…the location of the modern city of Peshawar in Pakistan, …

The rule of Kanishka, the second great Kushan emperor and fifth Kushan king, who reigns from around 127, is administered from two capitals: Purushapura (now Peshawar in northern Pakistan) and …