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.
Circle of the Rhine
The Rhine Circle largely covered the same area as the present Palatinate region, which lies west of the Rhine in the south of the German state of Rhineland-Palatinate, but included additionally the districts of and . These were incorporated into the Saar region after the end of the First World War and merged in 1974 into the . After the Second World War there were smaller losses of territory to the , especially in the area of . As part of the 1969 land reform the region designated as the Palatinate with Rhineland-Palatinate had its northern border changed somewhat. The Diocese of Speyer and the Evangelical Church of the Palatinate still exist today largely based on the historic boundaries of the Circle of the Rhine.