Reichskommissariat (English: literally Realm Commissariat; plural Reichskommissariate) is the German designation for a type of administrative office headed by a government official known as a Reichskommissar (English: Realm Commissioner). Although many different such offices existed primarily throughout the Imperial German and Nazi periods in a number of different fields (such as public infrastructure, spatial planning, ethnic cleansing, etc.) it is most commonly used to refer to the quasi-colonial territorial units established by Nazi Germany in several occupied countries during World War II. While officially located outside of the German Reich in a legal sense, these entities were directly controlled by their supreme civil authorities (the Reichskommissars), who ruled their assigned territories as German governors on behalf of and as direct representatives of Adolf Hitler.