This study is based on the states that represented the political will of the civilization-forming cultural basin of Khorasan–Azerbaijan in the post-Islamic period. Classical power structures and political identities formed in this geography are analyzed, revealing the historical roots of modern Iran, Turkey, and the states of Central Asia. The region is emphasized as a historical center of civilization, with Turks identified as the main formative element. The formation of Persian alongside Turkic as a political and cultural medium of communication, and its elevation to the status of a state language by Muslim Turkic polities, is evaluated as a historical reaction to the Arab-centered supremacy of the Umayyad period. It is argued that Persian identity was a later political construct and that the ancient population largely consisted of Turkic-Tat communities.

From the sixteenth century onward, the incorporation of the Ottoman Empire and Tsarist Russia into the Rum civilizational sphere weakened the political will of this basin, while twentieth-century nation-state formation fragmented its historical unity and narrowed its cultural space. The political and cultural legacy of the Khazars, Samanids, Ghaznavids, Seljuks, Khwarazmshahs, Ilkhanids, Timurids, Qara Qoyunlu, Aq Qoyunlu, Safavids, Afsharids, and Qajars is analyzed.

The region is presented as a Turkic-Islamic cultural center whose identity was transformed by modern nation-building processes. Contemporary issues—including the rights of Iranian Turks, Azerbaijan’s regional role, Turkey’s integration policies, South Caucasus geopolitics, and Russian influence—are assessed. The revival of the Khorasan/Azerbaijan civilizational basin is highlighted as strategically significant for the Eurasian balance of power, and strengthened cooperation among Turkic states is seen as a basis for an integrated and stable Turkic Union. The research is based on an extensive archival review and uses a positivist-interpretative methodology.