بر اساس کتاب‌های «آشنایی با تاریخ زبان‌های ایرانی» نوشته کوروش صفوی و «تاریخ مختصر زبان فارسی» نوشته محسن ابوالقاسمی و منابع متعدد دیگر، در طول تاریخ، زبان‌های زیر در ایران رایج بوده‌اند:https://www.isna.ir/news/92111107050/سرنوشت-زبان-های-ایرانی-از-هخامنشیان-تا-امروزhttps://www.irannamag.com/article/ریشه-های-زبان-فارسی-ادبی/http://parsianjoman.org/?p=5213Stolper, Matthew W. 2008. "Elamite". In "The Ancient Languages of Mesopotamia, Egypt, and Aksum". p. 47-50. p. 457.Kent, R. G. : "Old Persian: Grammar Texts Lexicon", page 6. American Oriental Society, 1950."Everyday text shows that Old Persian was probably more commonly used than previously thought". Accessed September 2010 from Richard N. Frye, "The History of Ancient Iran", (Ballantyne Ltd, 1984), 164. "Persian Prose Literature." World Eras. 2002. HighBeam Research. (September 3, 2012);""Princes, although they were often tutored in Arabic and religious subjects, frequently did not feel as comfortable with the Arabic language and preferred literature in Persian, which was either their mother tongue—as in the case of dynasties such as the Saffarids (861–1003), Samanids (873–1005), and Buyids (945–1055)..."". Elton L. Daniel, "History of Iran", (Greenwood Press, 2001), 74.Homa Katouzian, "Iranian history and politics", Published by Routledge, 2003. pg 128: ""Indeed, since the formation of the Ghaznavids state in the tenth century until the fall of Qajars at the beginning of the twentieth century, most parts of the Iranian cultural regions were ruled by Turkic-speaking dynasties most of the time. At the same time, the official language was Persian, the court literature was in Persian, and most of the chancellors, ministers, and mandarins were Persian speakers of the highest learning and ability""C.E. Bosworth, "Turkish Expansion towards the west" in "UNESCO History of Humanity", Volume IV, titled "From the Seventh to the Sixteenth Century", UNESCO Publishing / Routledge, p. 391: "While the Arabic language retained its primacy in such spheres as law, theology and science, the culture of the Seljuk court and secular literature within the sultanate became largely Persianized; this is seen in the early adoption of Persian epic names by the Seljuk rulers (Qubād, Kay Khusraw and so on) and in the use of Persian as a literary language (Turkish must have been essentially a vehicle for everyday speech at this time).""Concise Encyclopedia of Languages of the World", Ed. Keith Brown, Sarah Ogilvie, (Elsevier Ltd. , 2009), 1110; "Oghuz Turkic is first represented by Old Anatolian Turkish which was a subordinate written medium until the end of the Seljuk rule."Kathryn Babayan, "Mystics, monarchs, and messiahs: cultural landscapes of early modern Iran", (Harvard Center for Middle Eastern Studies, 2003), 14.Bobodzhan Gafurovich Gafurov, "Central Asia:Pre-Historic to Pre-Modern Times", Vol.2, (Shipra Publications, 1989), 359.* Manz, Beatrice Forbes (1999). "The Rise and Rule of Tamerlane". Cambridge University Press, p.109. . . p.109. "In almost all the territories which Temür incorporated into his realm Persian was the primary language of administration and literary culture. Thus the language of the settled 'divan' was Persian."* B.F. Manz, W.M. Thackston, D.J. Roxburgh, L. Golombek, L. Komaroff, R.E. Darley-Doran. "Timurids" Encyclopaedia of Islam Brill Publishers 2007; "During the Timurid period, three languages, Persian, Turkish, and Arabic were in use. The major language of the period was Persian, the native language of the Tajik (Persian) component of society and the language of learning acquired by all literate and/or urban Turks. Persian served as the language of administration, history, belles lettres, and poetry."* "Like his father, Olōğ Beg was entirely integrated into the Persian Islamic cultural circles, and during his reign Persian predominated as the language of high culture, a status that it retained in the region of Samarqand until the Russian revolution 1917 ... Ḥoseyn Bāyqarā encouraged the development of Persian literature and literary talent in every way possible ... * Robert Devereux (ed.) "Muhakamat Al-Lughatain (Judgment of Two Languages)" Mir 'Ali Shir Nawāi; Leiden, E.J. Brill 1966: "Nawa'i also employs the curious argument that most Turks also spoke Persian but only a few Persians ever achieved fluency in Turkic. It is difficult to understand why he was impressed by this phenomenon, since the most obvious explanation is that Turks found it necessary, or at least advisable, to learn Persian – it was, after all, the official state language – while Persians saw no reason to bother learning which was, in their eyes, merely the uncivilized tongue of uncivilized nomadic tribesmen. * David J. Roxburgh. "The Persian Album, 1400–1600: From Dispersal to Collection". Yale University Press, 2005. pg 130: "Persian literature, especially poetry, occupied a central in the process of assimilation of Timurid elite to the Perso-Islamicate courtly culture, and so it is not surprising to find Baysanghur commissioned a new edition of Firdawsi's Shanama."https://books.google.com/books?id=7J5IAAAAMAAJ&dq=کریم+خان+زند&focus=searchwithinvolume&q=ایل+زندHoma Katouzian, "State and Society in Iran: The Eclipse of the Qajars and the Emergence of the Pahlavis", published by I. B. Tauris, 2006. pg 327: "In post-Islamic times, the mother-tongue of Iran's rulers was often Turkic, but Persian was almost invariably the cultural and administrative language."Homa Katouzian, "Iranian history and politics", published by Routledge, 2003. pg 128: "Indeed, since the formation of the Ghaznavids state in the tenth century until the fall of Qajars at the beginning of the twentieth century, most parts of the Iranian cultural regions were ruled by Turkic-speaking dynasties most of the time. At the same time, the official language was Persian, the court literature was in Persian, and most of the chancellors, ministers, and mandarins were Persian speakers of the highest learning and ability.""Ardabil Becomes a Province: Center-Periphery Relations in Iran", H. E. Chehabi, "International Journal of Middle East Studies", Vol. 29, No. 2 (May, 1997), 235; "Azeri Turkish was widely spoken at the two courts in addition to Persian, and Mozaffareddin Shah (r. 1896-1907) spoke Persian with an Azeri Turkish accent."; "In the 19th century under the Qajars, when Turkish was used at court once again, literary activity was intensified."