This article, based on a lesser-known archival collection titled Mokātibāt-e Mokhtalefa, revisits the siege of Baghdad in 1036 AH during the reign of Shah Abbas I. Unlike most previous studies, which have largely relied on historiographical sources, this research analyzes diplomatic correspondence exchanged between Zainal Khan Shamlu, the Qizilbash commander-in-chief, and Hafez Ahmad Pasha, the Ottoman grand vizier, in order to examine the diplomatic and military dimensions of this event through primary documentary evidence. These correspondences, consisting of nine letters written in Turkish, provide access to a different level of information, including military strategies, decision-making logic, and the psychological atmosphere within the opposing camps.

The findings indicate that the siege of Baghdad was not merely a military confrontation, but also a complex arena of diplomatic interaction, prestige rivalry, and religious legitimization between the Safavids and the Ottomans. While Qizilbash forces sought to draw the Ottoman army into direct engagement, the Ottomans relied on a strategy of siege warfare and attrition, avoiding direct confrontation. The analysis of the correspondence further reveals that, as the siege prolonged and the Ottoman position weakened, the tone of the letters shifted from challenge and provocation toward conciliation and managed withdrawal.

This article argues that the letters in Mokātibāt-e Mokhtalefa not only complement existing historiographical narratives but, in some cases, enable a more precise reconstruction of the political and military logic of the event. It therefore highlights the necessity of greater attention to diplomatic correspondence in the study of Safavid–Ottoman relations.