Rhineland-Palatinate
The state of Rhineland-Palatinate was founded shortly after the Second World War on 30 August 1946. It was formed mainly from the southern part of the Prussian Rhine Province (the "Regierungsbezirke" of Koblenz and Trier), from Rhenish Hesse, from the western part of Nassau and the Bavarian Rhenish Palatinate minus the county of Saarpfalz. The Joint German-Luxembourg Sovereign Region ("Gemeinschaftliches deutsch-luxemburgisches Hoheitsgebiet") is the only unincorporated area of the state of Rhineland-Palatinate. This condominium is formed by the rivers Moselle, Sauer, and Our, where they run along the border between Luxembourg and Rhineland-Palatinate or the Saarland.
Bavaria
The Rhenish Palatinate was detached from Bavaria in 1946 and made part of the new state Rhineland-Palatinate. During the Cold War, Bavaria was part of West Germany. In 1949, the Free State of Bavaria chose not to sign the Founding Treaty ("Gründungsvertrag") for the formation of the Federal Republic of Germany, opposing the division of Germany into two states, after World War II. The Bavarian Parliament did not sign the Basic Law of Germany, mainly because it was seen as not granting sufficient powers to the individual "Länder", but at the same time decided that it would still come into force in Bavaria if two-thirds of the other "Länder" ratified it. All of the other "Länder" ratified it, and so it became law.