As recent scholarship has shown, most of East Central Europe remained at war for several years after the official armistice in November 1918, complicating the transition from empires into nation-states. This article addresses another aspect of the state-building process. As opposed to centralising power emanating from capitals such as Prague, Warsaw and Budapest, I argue that local politicians and village leaders made their own territorial and sovereignty claims. Rather than whole nations, it was small communities that first defined self-determination. Here I present a loose typology of such localities (ethno-linguistic republics, non-Bolshevik workers’ councils, and radical agrarians), and show that conflicts between mini-states and burgeoning nation-states shaped the development of the latter.