Nishapur, a major early Islamic mint center, played an unparalleled role in the political history of the eastern Islamic world. However, the traditional narrative relies mainly on later written accounts affected by omissions and contradictions. This study reconstructs a more precise political history of Nishapur from the death of Hārūn al-Rashīd (193 AH/809 CE) to the early 5th century AH. Using a comparative historical method centered on numismatics, it systematically compares data from 77 Nishapur coins with reports from traditional sources. The main question is: what new, complementary, or corrective information do the coins provide regarding the succession of rulers, power relations, and ideological transformations in this city? The findings reveal: first, six previously unknown governors (including 'Uthmān and Naṣr b. Saʿd) are identified. Second, established claims — such as Frye's assertion that “all Tahirid coins bear the caliph's name” — are refuted, and the absence of any coin bearing Yaʿqūb b. al-Layth al-Ṣaffār's name challenges the narrative of his domination over Nishapur. Third, the dates of honorific titles (Dhū al-Yamīnayn) and key events (the rise of Rāfiʿ b. Harthama, the blinding of Manṣūr b. Nūḥ) are determined more precisely. Fourth, ideological transformations are documented in Zaydi 'Alid coins (omission of the caliph's name) and in the Ismaili coin of Ḥusayn b. 'Alī al-Marwarrūdhī (pledging allegiance to the Fatimid caliph). The results confirm that comparative analysis of Nishapur's coin legends with historical texts plays a decisive role in reconstructing a detailed political history of Nishapur.