Turan (Tūiriiānəm, Tūrān; Turân, thuːˈɾɒːn, "The Land of Tur") is a historical region in Central Asia. The term is of Iranian origin and may refer to a particular prehistoric human settlement, a historic geographical region, or a culture. The original Turanians were an Iranian tribe of the Avestan age.
In ancient Iranian mythology, Tūr or Turaj (Tuzh in Middle Persian) is the son of the emperor Fereydun. According to the account in the Shahnameh, the nomadic tribes who inhabited these lands were ruled by Tūr. In that sense, the Turanians could be members of two Iranian peoples both descending from Fereydun, but with different geographical domains and often at war with each other. Turan, therefore, comprised five areas: the Kopet Dag region, the Atrek valley, parts of Bactria, Sogdia and Margiana.
A later association of the original Turanians with Turkic peoples is based primarily on the subsequent Turkification of Central Asia, including the above areas. According to C. E. Bosworth, however, there was no cultural relationship between the ancient Turkic cultures and the Turanians of the Shahnameh.
The oldest existing mention of Turan is in the Farvardin yashts, which are in the Young Avestan language and have been dated by linguists to about 2500 years ago. According to Gherardo Gnoli, the Avesta contains the names of various tribes who lived in proximity to each other: "the Airyas [Aryans], Tuiryas [Turanians], Sairimas [Sarmatians], Sainus [Sacae] and Dahis [Dahae]". In the hymns of the Avesta, the adjective Tūrya is attached to various enemies of Zoroastrism like Fraŋrasyan (Shahnameh: Afrāsīāb). The word occurs only once in the Gathas, but 20 times in the later parts of the Avesta. The Tuiryas as they were called in Avesta play a more important role in the Avesta than the Sairimas, Sainus and Dahis. Zoroaster himself hailed from the Airya people but he also preached his message to other neighboring tribes.