Tokharistan in the context of "Tocharian languages"

The Muslim conquests of Afghanistan began during the Muslim conquest of Persia as the Arab Muslims expanded eastwards to Khorasan, Sistan and Transoxiana. Fifteen years after the battle of Nahāvand in 642 AD, they controlled all Sasanian domains except in Afghanistan. Fuller Islamization was not achieved until the period between 10th and 12th centuries under Ghaznavid and Ghurid dynasties who patronized Muslim religious institutions.

Khorasan and Sistan, where Zoroastrianism was well-established, were conquered. The Arabs had begun to move towards the lands east of Persia in the 7th century. The Muslim frontier in modern Afghanistan had become stabilized after the first century of the Lunar Hijri calendar as the relative importance of the Afghan areas diminished. From historical evidence, it appears Tokharistan (Bactria) was the only area conquered by Arabs where Buddhism heavily flourished. Balkh's final conquest was undertaken by Qutayba ibn Muslim in 705.

Balkh is a town in the Balkh Province of Afghanistan. It is located approximately 20 kilometres (12 mi) to the northwest of the provincial capital city Mazar-i-Sharif and approximately 74 kilometres (46 mi) to the south of the Amu Darya and the Afghanistan–Uzbekistan border. In 2021–2022, the National Statistics and Information Authority reported that the town had 138,594 residents. Listed as the eighth largest settlement in the country, unofficial 2024 estimates set its population at around 114,883 people.

Historically, the site of present-day Balkh was held in considerably high regard due to its religious and political significance in Ariana. A hub of Zoroastrianism and Buddhism, the ancient city was also known to the Persians as Zariaspa and to the Greeks as Bactra, giving its name to Bactria. As such, it was famously known as the capital of Bactria or Tokharistan. The Italian explorer and writer Marco Polo described Balkh as "a noble city and a great seat of learning" prior to the Mongol conquests. Most of the town now consists of ruined buildings, situated some 12 kilometres (7.5 mi) from the right bank of the seasonally flowing Balkh River, at an elevation of about 365 metres (1,198 ft).

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 Tocharians or Tokharians (US: /toʊˈkɛəriənˌ -ˈkɑːr-/ toh-KAIR-ee-ən, -⁠KAR-; UK: /tɒˈkɑːriən/ to-KAR-ee-ən) were speakers of the Tocharian languages, a group of Indo-European languages known from around 7,600 documents from the 6th and 7th centuries, found on the northern edge of the Tarim Basin (modern-day Xinjiang, China). The name "Tocharian" was given to these languages in the early 20th century by scholars who identified their speakers with a people known in ancient Greek sources as the Tókharoi (Latin: Tochari), who inhabited Bactria from the 2nd century BC. This identification is now generally considered erroneous, but the name "Tocharian" remains the most common term for the languages and their speakers. Their endonym is unknown, although they may have referred to themselves as the Agni, Kuči, and Krorän or as the Agniya and Kuchiya known from Sanskrit texts.

Agricultural communities first appeared in the oases of the northern Tarim circa 2000 BC. Some scholars have linked these communities to the Afanasievo culture found earlier (c. 3500–2500 BC) in Siberia, north of the Tarim or Central Asian BMAC culture. The earliest Tarim mummies date from c. 1800 BC, but it is unclear whether they are connected to the Tocharians of two millennia later. This once theorized ancestry between Tocharians and these mummies is however now largely considered to be discredited by the absence of a genetic connection with Indo-European-speaking migrants, particularly the Afanasievo or BMAC cultures.

Abū Ḥafṣ Qutayba ibn Abī Ṣāliḥ Muslim ibn ʿAmr al-Bāhilī (Arabic: أبو حفص قتيبة بن أبي صالح مسلم بن عمرو الباهلي; 669–715/6) was an Arab commander of the Umayyad Caliphate who became governor of Khurasan and distinguished himself in the conquest of Transoxiana during the reign of al-Walid I (705–715). A capable soldier and administrator, he consolidated Muslim rule in the area and expanded the Caliphate's border to include most of Transoxiana. From 705 to c. 710, he consolidated Muslim control over the native principalities of Tokharistan and conquered the principality of Bukhara, while in 710–712 he conquered Khwarizm and completed the conquest of Sogdiana with the capture of Samarkand. The latter opened the road to the Jaxartes valley, and during the last years of his life Qutayba led annual campaigns there, extending Muslim control up to the Fergana Valley and parts of Chinese Turkestan.

To increase his strained manpower, Qutayba initiated the wide-scale levy of native Khurasani and Transoxianian soldiers who fought alongside the Arab Muslim troops. Following Walid's death, Qutayba, insecure of his position under the new regime, rebelled but failed to secure the support of his army, and was killed. Most of his conquests in Transoxiana were lost in the years after his death; only in the 740s was the Muslim position restored to the line reached by Qutayba, and only after the Battle of Talas in 751 did the region come solidly under Muslim control.

The Kushan Pass or Kaoshan Pass (el. about 4,370 m or 14,340 ft) is a mountain pass just west of the famous Salang Pass (3,878 m. or 12,723 ft.) in the Hindu Kush mountain range of northern Afghanistan. These two passes provided the most direct, if difficult, routes across the imposing east–west wall of the Hindu Kush mountains which divide northern Afghanistan or Tokharistan from Kabul province, which is closely connected to southern Afghanistan and Pakistan. Nowadays, the Salang tunnel constructed by the Soviets in the 1960s, and the paved road through it make it by far the easiest route through the Hindu Kush Mountains.

Vincent Smith states that Alexander the Great took his troops across both the Khawak Pass and the Kaoshān or Kushan Pass.

Peroz I (Middle Persian: 𐭯𐭩𐭫𐭥𐭰, romanized: Pērōz) was the Sasanian King of Kings (shahanshah) of Iran from 459 to 484. A son of Yazdegerd II (r. 438–457), he rejected the rule of his elder brother and incumbent king Hormizd III (r. 457–459), eventually seizing the throne after a two-year struggle. His reign was marked by war and famine. Early in his reign, he successfully quelled a rebellion in Caucasian Albania in the west, and put an end to the Kidarites in the east, briefly expanding Sasanian rule into Tokharistan, where he issued gold coins with his likeness in Balkh. At the same time Iran was suffering from a seven-year famine. He soon clashed with the former subjects of the Kidarites: the Hephthalites, who possibly would have helped him gain the throne initially. He was defeated and captured twice by the Hephthalites and as a result lost his recently acquired gains.

In 482, revolts broke out in the western provinces of Armenia and Iberia, led by Vahan Mamikonian and Vakhtang I respectively. Before Peroz could quell the unrest there, he was defeated and killed in his third war with the Hephthalites in 484, who seized the main Sasanian cities of the eastern region of Khorasan−Nishapur, Herat and Marw. Taking advantage of the weakened Sasanian position in the east, the Nezak Huns subsequently seized the region of Zabulistan. Peroz was the last shahanshah to mint unique gold coins in the Indian region of Sindh, which indicates that the region was lost around the same period. Albeit a devout Zoroastrian, Peroz supported the newly established Christian sect of Nestorianism, and just before his death, it was declared the official doctrine of the Iranian church.