Pleissnerland

Pleissnerland, Pleissenland or the Imperial Territory of Pleissenland (German: Reichsterritorium Pleißenland; Latin: Terra Plisensis) was a Reichsgut of the Holy Roman Empire, which meant that it was directly possessed by the respective elected King of the Romans or Emperor. It was named for the Pleiße River, and was located in what is now the border region between the German states of Thuringia and Saxony south of Leipzig, including the towns of Altenburg, Chemnitz, Zwickau and Leisnig.

The area east of the Sorbian March was conquered between 927 and 929 by King Henry I of Germany in the course of his campaign against the Polabian Slavs, it was incorporated as Gau Plisni into the Saxon Marca Geronis. Upon the weakening of the Imperial authority during the 11th century Investiture Controversy, the estates gradually came under the rule of local comital dynasties, foremost the Burgraves of Nuremberg and the Margraves of Meissen.

Emperor Lothair III (1133-1137) began to reassert his claims by repeatedly choosing the Kaiserpfalz at Altenburg (Castro Plysn) as his temporary residence and by promoting the colonization the surrounding estates up to the Ore Mountains in the course of the Ostsiedlung, including the foundation of the Benedictine abbey of Chemnitz. He also seized parts of the homelands of the Lusatian Margrave Henry of Groitzsch, who had died without heirs in 1135. The Reichsgut gained in importance with the accession of King Conrad III of Germany from the House of Hohenstaufen in 1138: As Conrad's elder brother Duke Frederick II of Swabia held the Swabian home territories of the Hohenstaufen dynasty, the King had to rely on the Pleissnerland around the Altenburg Kaiserpfalz as a personal allodium in his quarrels with the mighty Bavarian duke Henry the Proud and his successors from the House of Welf.

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