The Tocharians are the Tocharian-speaking inhabitants of the Tarim Basin, making them the easternmost speakers of Indo-European languages in antiquity.

After wars against the northern Xiongnu Empire, the Tocharians migrate out of the Tarim Basin, and the Indo-European language of the Tocharians becomes supplanted by the languages of the Xiongnu.

A later group of Tocharians are the Kushans and maybe some Iranian tribes of the Hephthalites whose Iranian population also settles in modern Afghanistan, North-Eastern Iran, Uzbekistan, Tajikistan and Turkestan.

The Takhar province of Afghanistan is named after Tocharians.

Tocharian languages remain in the region until replaced in 800 by the Altaic languages, with the arrival of Turkic migration from present Mongolia.