Nordgau

The March of the Nordgau (German: Markgrafschaft Nordgau) or Bavarian Nordgau (Bayerischer Nordgau) was a medieval administrative unit (Gau) on the frontier of the German stem duchy of Bavaria. It comprised the region north of the Danube and Regensburg (Ratisbon), roughly covered by the modern Upper Palatinate stretching up to the river Main and, especially after 1061, into the Egerland on the border with Bohemia.

The area east of Franconia proper up to the Bohemian Forest had been settled by Germanic Varisci and Armalausi tribes in ancient times; after the Migration Period it was occupied by the Merovingian king Chlodio. From the mid 6th century onwards, the region was Christianised by several wandering bishops, among them Saints Boniface and Emmeram of Regensburg. In 739, the Diocese of Regensburg was founded. The great fortress of Wogastisburg was built at the insistence of Saint Boniface by Charles Martel.

When King Charlemagne deposed Duke Tassilo III of Bavaria in 788, he entered the Nordgau and brought the Carolingian Empire into contact with Bohemia permanently. For this reason, the incorporated Nordgau has been called the Bohemian March on occasion, although this term is also reserved for the later Margraviate of Moravia. By a 806 deed issued at Thionville, Charlemagne separated the Bavarian lands left of the Danube including the ducal residences of Regensburg and Lauterhofen, called pagum, qui dicitur Northgowe. His chancellor Einhard reached the confirmation by Pope Leo III.

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