North Rhine-Westphalia (Nordrhein-Westfalen in German) is the most populous and most economically important state in Germany. The state was formed in 1946 by the merger of the Prussian provinces of northern Rhineland and Westphalia.
With a a population of 18,033,000 inhabitants, North Rhine-Westphalia would be the fifth most populous country in Western Europe, after France, the UK, Italy and Spain. The Rhine-Ruhr metropolitan region, which occupies most of the North Rhineland section of the state, is the main population centre with over 11 million inhabitants. It comprises among others the cities of Bonn, Cologne, Düsseldorf, Mönchengladbach, Duisburg, Essen and Dortmund. Its population density is a staggering 1,422 inhabitants per km² (3,684/sq mi), 3.5 times more than the (already packed) neighbouring Netherlands and Belgium, and over 4 times the German average.
North Rhine-Westphalia has a surface area of 34,084 km², just in between that of Belgium and the Netherlands, and scarcely bigger than the U.S. state of Maryland.
Before the dissolution of the Holy Roman Empire in 1806, what is now North Rhine-Westphalia was composed of the Free Imperial City of Aachen, the Duchy of Jülich, the Duchy of Kleve, the Archbishopric of Cologne, the Free Imperial City of Dortmund, the Duchy of Berg, the County of Mark, the Prince-Bishopric of Münster, the Duchy of Westphalia, and the Bishopric of Paderborn.
Many famous German beers are brewed in North Rhine-Westphalia, including Dortmunder Export, Kölsch, König, Krombacher, Veltins, and Warsteiner (Germany's largest privately owned brewery).
Famous people from North Rhine-Westphalia include (chronologically): the composer Ludwig van Beethoven, the poet Heinrich Heine, the industrialist Alfred Krupp, the social scientist and political theorist Friedrich Engels, the physicist Wilhelm Röntgen, Chancellor Konrad Adenauer, Chancellor Gerhard Schröder, the F1 driver Michael Schumacher, the model Claudia Schiffer, and the model and actress Heidi Klum.