During their reign, many distinct areas of the Persian empire (which they had taken over) were influxed with heavy populations of Turks and many parts remained Persian. For example, Esfahan, which is a Persian-speaking city in central Iran, was a Seljuk capital for many years but the people's language was never changed and the ethnic structure of the people of the city of Esfahan remained Persian. Other places such as Khorasan (northeastern Iran) as well as Azerbaijan, however, were places within the Persian empire which became home to a large number of Turks who changed the ethnic structure of the original inhabitants. This rejects the claim of pan-Iranists who state that the eminent amount of Turkish migrants in the 11th-12th centuries only changed the linguistics of the original inhabitants of Iran. If this was the case, then how come many other parts of the ancient Persian empire as well as distinct parts of the Middle East that were ruled by Turks did not see linguistic change? Pan-Iranists also claim that the Turkish race is infact a Mongoloid race which also includes some peoples of east and central Asia such as Mongols, Koreans, Japanese and others. .

             Such false statements which go against archeological and historical evidence are partially made because the Turkish language is part of the Ural-Altaic language family group which also includes Mongolian but which also includes European languages such as Finnish and Hungarian. Archeological evidence proves that the original homeland of the Oghuz Turks was an area north of the Oxus river in present day Kazakstan (central Asia) and that they spread in an area between the Caspian sea and Aral lakes within a time frame prior to their migration west to the Middle East and Europe. Turkish languages have very slight similarity to languages such as Mongolian, Finnish and Hungarian and there is no way that a Mongol could understand an Azeri by merely listening to his/her speech.