Viking raids in the Rhineland
The area known today as the Rhineland begins at the confluence of the Moselle and the Rhine and ends at Emmerich, where the Rhine divides into the Lek and the Waal to form a delta. In the east, the Rhineland ends close to the Rhine itself, being bounded by low mountain ranges such as the Siebengebirge or Bergisches Land. To the west its boundary is less well defined, but in general parlance it runs beyond the present state border with the Netherlands, i.e. east of the Meuse. Because the modern state of Rhineland-Palatinate lies south of the Moselle, the low mountain range of the Eifel north of the river is usually seen as belonging to the Rhineland. Areas south of the Moselle, such as the Hunsrück, are also considered to be part of the Rhineland.
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.