This introductory chapter provides an overview of Warsaw during the Great War. Warsaw entered the war not as a capital city but as the third city of the Russian Empire. In the war's first year, Warsaw witnessed massive shifts in population as a consequence of mobilization, evacuations, deportations, and male labor out-migration on the one hand, and the arrival of refugees and wounded soldiers in the other. By the second winter of the war, the city experienced rapidly escalating incidences of starvation, disease, death, and conflict over the increasingly scarce resources necessary to sustain human life. The chapter then compares Warsaw's experience of the Great War to that of the Second World War.