The "Great War" forever changed the map of the world. Military occupations, postwar mandates, and plebiscites created numerous new governments. From the disintegration of the Russian, Ottoman, and Austro-Hungarian empires emerged newly-independent nations, while nationalist and irredentist movements took advantage of the chaos to claim sovereign territory.
Whatever their origins, and no matter how long- or short-lived these new governments were destined to be, they all announced their arrival by issuing postage stamps. Enjoy this selection of stamps related to World War I and its aftermath. Most are displayed in the National Postal Museum's permanent exhibition, A Stamp for Every Country.