The Iranian-Mongol legitimacy of the Timorid dynasty was not merely a transfer of rulers; rather, it encompassed a comprehensive reorientation. One of the immediate consequences of this event was the revival of the Iranian identity within its independent geographical domain. Despite the vast and diverse territories, this process also reflected the grandeur of Iran’s past empires. This transformation not only provided the new conquerors with an opportunity to recognize and assimilate their identity with it but also created a foundation for Iranians to strengthen their self-awareness and identity in response to the Timorid conquests. Therefore, maintaining and consolidating the monarchy, addressing crises and challenges arising from the instability of power, and overcoming legitimacy-related issues were the primary concerns of the Timorids. This study seeks to answer the question: What were the criteria for the legitimacy of the Timorid dynasty in the historiographical thought of Taj al-Salmani? Using content analysis, the research concludes that dynastic historiography during the Timorid period was deeply intertwined with and influenced by ruling power. In Timorid society, the strong need of the Timorid princes to attain legitimacy set the historiographical trend of this period apart from other historical periods. In this political and social context, Taj al-Salmani’s primary motivation was to grant legitimacy and succession rights to Shahrukh and his descendants based on the belief in the divine rights of rulers and the sanctity of governance among Iranians, which had always been considered a key factor in legitimizing rulership.