The year 1722 was a long one for the decision-makers in Istanbul, as the Ghilzai Afghans overthrew the Safavids after an eight-month siege of Isfahan, and the Russians occupied Darband on the Caspian coast of the Caucasus. By examining the decision-making process of the Sublime Porte and the eventual diplomatic formulations of the decisions taken that year through Ottoman and European sources of the time, this paper argues that the Ottoman sultan’s title of caliph, denoting the supreme political leadership of the global Muslim community, functioned as a subtle and powerful diplomatic tool to support the legitimacy of the Ottoman political positions in the interstate arena. The Porte saw the Afghan and Russian advances as a major threat to its eastern borders, which had been secure since the Treaty of Zuhab (1639) with the Safavids. Thus, the Ottomans had no intention of breaking the peace with the Iranians. However, Shah Sultan Husayn’s vulnerability led the Ottomans to decide on a military incursion into Iranian territory, primarily to safeguard Ottoman domains against the Afghans and the Russians once the Safavid Shah fell. Nevertheless, the Porte also considered the possibility of the Shah’s later return to the throne, and formulated a diplomatic discourse that would not portray the Ottoman Sultan as either a peacebreaker or someone who would exploit the Shah’s weakness for political greed. The formulation was that the Ottomans entered the Iranian provinces as a requirement of the Sultan’s title of caliph to protect the Sunni population living in Iran from the harm of the undisciplined and disorderly Afghan soldiers. In a broader context, the Ottoman resort to the title of caliph in the turbulent year of 1722 reveals two insights: First, beyond its symbolic claims to superiority, the title of caliph functioned as an invaluable practical diplomatic tool, giving its holder a wide margin of political maneuver by protecting the Ottomans from a potential Safavid “misunderstanding” of the Ottoman occupation of Iranian lands. Second, the Ottoman recourse to the title of caliph highlights the need to revise the common scholarly view that the Ottoman sultans did not use their title of caliph for political purposes for almost three centuries between the sixteenth and nineteenth centuries. In sum, Ottoman policymakers sought to navigate a complex military and political challenge by employing a religio-political diplomatic discourse within an expanded arena of diplomacy, prompted by these “misunderstandings.”