At the beginning of the
High Middle Ages the region now known as the Upper Palatinate was part of the
Bavarian March of the Nordgau. The region took its current name no earlier than the early 14th century. From the mid-13th century, much of the region was controlled by the
Wittelsbach dynasty and until 1329 was ruled by the Wittelsbach
Elector Palatine as part of the larger
County Palatine of the Rhine (). By the
1329 Treaty of Pavia, the Wittelsbach territories were divided between two branches of the dynasty. The territory around the Rhine river in the west became known as the Rhenish Palatinate () or Lower Palatinate, and is today usually known simply as
the Palatinate (); it is from this territory that the modern German state of
Rhineland-Palatinate derives its name. By contrast, the territory to the east centred on
Amberg became known as the Upper Palatinate (), upper and lower in this case referring to the elevation of the territories (compare
Low and
High German languages,
Upper and
Lower Lusatia,
Upper and
Lower Lorraine,
Low Countries,
Lower Saxony). Cadet branches of the Wittelsbach dynasty also ruled over smaller territories in
Neuburg and
Sulzbach. As a result of the Elector Palatine
Frederick V's abortive claim to the
Bohemian throne in 1619–1620, the Upper Palatinate, along with the rest of his lands, were declared forfeit to the Emperor and, along with the Electoral title, given to the
Duke of Bavaria. Although the Lower Palatinate was restored to Frederick's son by the
Peace of Westphalia in 1648, the Upper Palatinate remained under the Elector of Bavaria, and has remained a part of Bavaria ever since. The smaller territories of
Neuburg and
Sulzbach came to Bavaria in 1777 when
Charles Theodore, Elector Palatine inherited the Bavarian lands of his Wittelsbach cousin
Maximilian III Joseph, Elector of Bavaria. The city of
Regensburg, an
Imperial Free City, was not joined with the rest of the region until the end of the
Holy Roman Empire in 1806 and the end of the short-lived
Principality of Regensburg under
Carl von Dalberg, which existed from 1803 to 1810. After the founding of the
Kingdom of Bavaria, the state was totally reorganised, and in 1808, divided into 15 administrative districts (; singular '
) called ' (literally "Circles", singular: '
). They were created in the fashion of the French departments, quite even in size and population, and named after their main rivers. In the following years, due to territorial changes (e.g. the loss of Tyrol, the addition of the Palatinate), the number of ' in the kingdom was reduced to 8. One of these was the '
(Regen District). In 1837, king Ludwig I of Bavaria renamed the ' after historical territorial names and tribes of the area. This also involved some border changes or territorial swaps. Thus, the district name of Regenkreis was changed to Upper Palatinate. ==Districts==