North Rhine-Westphalia (Nordrhein-Westfalen) Historical Geography

Historical Background
North Rhine-Westphalia was established in 1946 after World War II from the Prussian provinces of Westphalia and the northern part of Rhine Province (North Rhine), and the Free State of Lippe by the British military administration in Allied-occupied Germany. North Rhine-Westphalia became a state of the Federal Republic of Germany in 1949, and the city of Bonn served as the federal capital until the reunification of Germany in 1990 and as the seat of government until 1999. [Wikipedia]

Maps
Germany was first unified as a nation in 1871. For German research prior to 1945, the Research Wiki, FamilySearch Catalog, and FamilySearch Historical Records are organized by the place names in use from 1871 to 1945.
 * To find the 1871 duchy or province for your town, use Meyer's 1871 Gazetteer Online.