West Germany is shown in blue, East Germany is shown in red, The Saar protectorate under French economic control is shown in green. The Ruhr Area, the industrial engine of West Germany, is shown in brown as it was to some extent under the control of the International Authority for the Ruhr. Pre-war German territory east of the Oder-Neisse line is shown in gray, because it was assigned to Poland or annexed by the Soviet Union.