There were many areas annexed by Nazi Germany both immediately before and throughout the course of World War II. Territories that were part of Germany before the annexations were known as the "Altreich".

In Nazi German terminology, Volksdeutsche were "people whose language and culture had German origins but who did not hold German citizenship". The term is the nominalised plural of volksdeutsch, with Volksdeutsche denoting a singular female, and Volksdeutscher, a singular male. The words Volk and völkisch conveyed the meanings of "folk".