The previous post argued that the “Persian” (or Farsi-speaking) provinces of Iran are not necessarily more prosperous and economically developed than the “non-Persian” provinces, focusing on the relatively affluent but non-Farsi-speaking Caspian region, particularly Mazandaran province. The Azeri-speaking (or Azerbaijani-speaking) northwestern region of Iran also economically ranks somewhat higher than average. It is, however, less economically developed than the neighboring Azeri-speaking country of Azerbaijan.

Rather than framing the issue of Iran’s uneven economic development around the distinction between Farsi- and non-Farsi speakers, it is better to organize it around the distinction between “core Iranian ethnic groups” and “non-core ethnic groups.” The Mazandaranis, for example, are not Farsi-speakers, but they are so integral to the Iranian nation that they have often been classified as “Persian.” The Wikipedia article on the Iranian province of Golestan, for example, claims that “The Mazandaranis who inhabit the foothills … were subsumed under the rubric ‘Persian’ by these official statistics.”
Although the Azeris, who speak a Turkic language, are never classified as Persians, they have been central players in the Iranian state and nation for centuries. According to many sources, Azeris are, if anything, over-represented in the country’s elite population. In the core provinces of Tehran and Alborz, Azeris constitute up to a quarter of the population. The actual percentage of Azeri-speakers in these provinces, however, is difficult if not impossible to determine due the prevalence of intermarriage and bilingualism. To be sure, cultural conflicts occasionally arise, such as the 2006 “cartoon cockroach controversy” analyzed in a previous GeoCurrents post. Overall, however, they are of little significance.
Although Azeri is in the Turkic language family, most of the inhabitants of “greater Azerbaijan” (northwestern Iran and independent Azerbaijan) seem to have spoken the Iranian language of Old Azeri (or Azari) up to the early-modern period. The region had been fully part of the Persian cultural sphere, and it largely remained so after the switch to a Turkic tongue.
For more information on this important region and its linguistic history, I recommend the blogpost “Turko-Iranica: The Shifting Faces of Iranian Azerbaijan and its Idiom,” by Afsheen Sharifzadeh. As this essay notes:
The “Old Azari” language–previously one of the major Iranian languages–comprised a sprachbund of dialects distributed in a broad range between lake Urmia in the west and the Caspian littoral in the east. Old Azari seems to have shared a genetic affinity with the ancestor of the modern Talysh language, and it further appears to form a broader group with the so-called “Northwestern” branch of Iranian including modern Gilaki, Māzanderāni, Semnāni, and Zaza-Gorani. Some linguists hold that the southern Tāti varieties of Iranian Azerbaijan … are peripheral remnants of Old Azari. As such, this language has been spoken in the region of Azerbaijan for at least three millennia.
…
It appears Old Azari only lost its status as the majority language between the 16th-17th centuries with the ascent of the Qizilbash-backed Safavids. The subsequent influx of numerous Turkic military elements into the region further spread Turkic at the detriment of Old Azari, which in turn receded and ceased to be used, at least in the major urban centers. Notwithstanding the city of Tabriz maintained a number of distinctly Old Azari-speaking neighborhoods well into the Safavid period with the poet Ruhi Anārjānī composing a compendium of the language as late as the 17th century. However by the turn of the 20th century the Turkification of Azerbaijan was near completion, with the old Iranic speakers found exclusively in remote recesses of the mountains or other isolated areas such as Harzand village in Marand. Lamentably, language shift is currently in progress and the remaining Tāti dialects face a state of attrition and imminent endangerment.
Afsheen Sharifzadeh also notes that the Azerbaijani dialects of northwestern Iran and independent Azerbaijan are currently diverging:
The Northern and Southern varieties of Azerbaijani are moderately mutually intelligible without training. Since, for several decades, there has been little, if any, cultural exchange between the two parts of Azerbaijan, the mutual intelligibility is decreasing. Today the two languages are remarkably distinct in phonology, morphology, syntax, and source of loanwords; purist efforts upon the Northern variety have uprooted numerous Persianisms in favor of Russianisms and revisionist Turkic models, while the Southern variety continues to rely upon Persian much as it has since its arrival to the region.


