This article explores religious practice among Buryats, a Siberian people, through scholarship on sovereignty and the body. Under conditions of rapid social transformation such as those that accompanied the Russian Revolution, the Cold War, and the dissolution of the Soviet Union, certain religious bodies became key sites through which Buryats have negotiated their relationship with the Russian state and the larger Tibeto‐Mongol and Eurasian Buddhist worlds. Despite the Russian government's continuing reluctance to see its subjects cross borders, Buryats have maintained their long‐standing mobility—across spatial borders of nation‐states and temporal horizons between life and death—by employing characteristically Buddhist “body politics” that can both conform to and diplomatically challenge Russian logics of political rule. Specific bodies constructed by some Buryat Buddhists as “ideal sovereigns”—bodies that are fluid, mobile across time and space, and transgressive of geopolitical borders and, ultimately, death—become metonymic for broader cosmic processes.