Großdeutschland, or 'Greater Germany,' refers to the political and nationalistic idea of unifying all German-speaking peoples and territories into a single nation-state. This concept emerged during the 19th century, particularly in the context of German nationalism, and was central to the ambitions of the German Empire in the early 20th century, driving expansionist policies and aspirations for unification through the annexation of Austria and other regions with ethnic German populations.