Tajiks (, Tājīk, Tājek; ) are a Persian-speaking Iranian ethnic group native to Central Asia, living primarily in Afghanistan, Tajikistan, and Uzbekistan. Tajiks are the largest ethnicity in Tajikistan, and the second-largest in Afghanistan and Uzbekistan. They speak varieties of Persian, a Western Iranian language. In Tajikistan, since the 1939 Soviet census, its small Pamiri and Yaghnobi ethnic groups are included as Tajiks. In China, the term is used to refer to its Pamiri ethnic groups, the Tajiks of Xinjiang, who speak the Eastern Iranian Pamiri languages. In Afghanistan, the Pamiris are counted as a separate ethnic group. As a self-designation, the literary New Persian term Tajik, which originally had some previous pejorative usage as a label for eastern Persians or Iranians, has become acceptable during the last several decades, particularly as a result of Soviet administration in Central Asia. Alternative names for the Tajiks are Eastern Persian, Fārsīwān (Persian-speaker), and Dīhgān (cf. ) which translates to "farmer or settled villager", in a wider sense "settled" in contrast to "nomadic" and was later used to describe a class of land-owning magnates as "Persian of noble blood" in contrast to Arabs, Turks and Romans during the Sassanid and early Islamic period. History The Tajiks are an Iranian people, speaking a variety of Persian, concentrated in the Oxus Basin, the Farḡāna valley (Tajikistan and parts of Uzbekistan) and on both banks of the upper Oxus, i.e., the Pamir Mountains (Mountain Badaḵšān, in Tajikistan) and northeastern Afghanistan (Badaḵšān). Historically, the ancient Tajiks were chiefly agriculturalists before the Arab Conquest of Iran. While agriculture remained a stronghold, the Islamization of Iran also resulted in the rapid urbanization of historical Khorasan and Transoxiana that lasted until the devastating Mongolian invasion. Several surviving ancient urban centers of the Tajik people include Samarkand, Bukhara, Khujand, and Termez. Contemporary Tajiks are the descendants of ancient Eastern Iranian inhabitants of Central Asia, in particular, the Sogdians and the Bactrians, and possibly other groups, with an admixture of Western Iranian Persians and non-Iranian peoples. According to Richard Nelson Frye, a leading historian of Iranian and Central Asian history, the Persian migration to Central Asia may be considered the beginning of the modern Tajik nation, and ethnic Persians, along with some elements of East-Iranian Bactrians and Sogdians, as the main ancestors of modern Tajiks. In later works, Frye expands on the complexity of the historical origins of the Tajiks. In a