Azerbaijani-Iranian relations are among the most complicated in the region, having experienced radical transformations over the last 20 years. Cordial friends and brotherly nations at the end of the Cold War, Baku and Tehran almost engaged in armed conflict a decade later and relations have since remained tense.
Several factors underlie the relations between the two states. The first is the presence in Iran of a 22-30 million strong Azerbaijani ethnic minority, the largest in the country. Ever since Azerbaijan’s independence, Iran has been suspicious that Baku might use the ethnic card to pressure Iran. Second, the secular nature of Azerbaijan’s regime annoys Tehran. Azerbaijan continues to be a model of development not only for Iranian Azerbaijanis but also for other ethnicities. [...]