The Netherlands, which literally means the Low Countries, lies in northern Europe. After being occupied by the French in the eighteenth century, the territory united with Belgium to form the Kingdom of the United Netherlands under William I in 1815. However, in 1830 Belgium withdrew from the union. Then during the Second World War the country was occupied by Germany. In 1948 the country entered into the Benelux economic union with Belgium and Luxembourg. Roman Catholicism and Protestantism are the main religions; Dutch is the official language.