Tun, one of the important cities of southern Khorasan and a dependency of Herat within the administrative divisions of the Safavid era, occupied a significant position in the political and military developments of Khorasan due to its geographical location and strategic importance. This study aims to explain the political-military transformations of Tun and examine the roles of the central government and local rulers in maintaining security and confronting Uzbek threats. The main question of the study is: What impact did Tun’s geographical location and defensive capacities have on its political-military position in the face of Uzbek attacks, and how did the central government and local rulers respond to these threats? The study hypothesizes that Tun’s strategic location along the communication routes of Khorasan and its defensive capacities increased its importance in the Safavid military strategy against the Uzbeks; nevertheless, the level of security and stability in the city was directly influenced by the strength of the central government and the capabilities of local rulers. The research employs a historical methodology based on library research. The findings indicate that the weakness of the central government, conflicts among the Qizilbash amirs, and intensified Uzbek attacks during the reign of Shah Mohammad Khodabandeh and the early years of Shah Abbas I led to insecurity, occupation, and economic and social damage in Tun. Following the consolidation of Shah Abbas I’s power, the strengthening of Safavid military presence in Khorasan, and the successive defeats of the Uzbeks, political security and stability were restored in Tun, creating conditions for its subsequent economic and urban development. Accordingly, the political-military transformations of Tun can be understood as the outcome of the interaction among three factors: the authority of the central government, the capabilities of local rulers, and the military pressure exerted by rival powers in eastern Iran.