This article historicizes and conceptualizes the Myanmar radical tradition: a tradition of thought and practice that has animated radical politics across Myanmar’s twentieth and twenty-first centuries. From anti-colonial struggle to decolonization, and from communist insurgency to left feminism, ethnic rebellion, and today’s revolutionary upsurge following the 2021 coup d’état, this radical tradition is best understood not as something bounded or solitary. Rather, it names a productive conjoining of radical thought and practice from within Myanmar, as well as from other times and places, beginning in the imperial world order of the early twentieth century. Revisiting scholarship on transatlantic and transpacific radicalisms, we argue that attention to imperialism offers important insights into Myanmar’s modern history and contemporary dynamics, including the Myanmar radical tradition. Yet, the Myanmar radical tradition—heterogeneous and internally conflictual, a site of historical dispute—also sheds light on the changing imperial world order, which we show has a fundamentally reactive, counter-revolutionary quality. Today’s late imperialism, we argue, can be seen as a retaliatory response to the long arc of decolonization, a story within which Myanmar’s contemporary revolutionary struggle renders the Myanmar radical tradition very much a living tradition.