Provinces
In the Middle Ages, the territory of Greater Iran was known to be composed of two portions: Persian Iraq (western portion) and Khorasan (eastern portion). The dividing region was mostly along with Gurgan and Damaghan cities. Especially the Ghaznavids, Seljuqs and Timurids divided their Empire to Iraqi and Khorasani regions. This point can be observed in many books such as "Tārīkhi Baïhaqī" of Abul Fazl Bayhqi, Faza'ilul al-anam min rasa'ili hujjat al-Islam (a collection of letters of Al-Ghazali) and other books. Transoxiana and Chorasmia were mostly included in the Khorasanian region.
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