Kreis Wirsitz

Kreis Wirsitz was one of 14 or 15 Kreise (English: counties) in the northern administrative district of Bromberg, in the Prussian province of Posen. The county existed with essentially the same boundaries beginning in 1815 as a German Kreise then from 1919 as a Polish Powiat until 1975. Its administrative center was the town of Wyrzysk (Wirsitz). The county contained additional municipalities such as Bialosliwie, Lobzenica (Lobsens), Miasteczko Krajeńskie (Friedheim), Mrocza (Mrotschen), Nakło nad Notecią (Nakel), Sadki and Wysoka (Wissek) plus over 100 villages. Many villages that had Germanic names were changed to completely different Polish names following World War II, such as Radzicz (formerly Hermannsdorf). In 1954 the central government abolished the commune (Polish: gmina) as the smallest unit of government, dividing the county into 28 clusters. In 1973 municipalities were restored. After the administrative reform of 1975, the territory of the county was divided between the new (lower) region of Bydgoszcz and the region Piła. The territory of the defunct county was annexed by Naklo County, Kujawy-Pomerania Province and Pila County, Wielkopolska Province. The county was not restored in the year 1999 and Wyrzysk was incorporated into Pila County.

The area around the town of Wyrzysk, then part of the Duchy of Warsaw, became part of the Grand Duchy of Posen on May 15, 1815 as accorded at the Congress of Vienna. The rather titulary Grand Duchy of Posen, held by the Hohenzollern, the ruling family in the Kingdom of Prussia, was in fact an autonomous province within Prussia, but not belonging to those territories covered by the loose league called the German Confederation. Its constitutional peculiarity had been abolished on December 5, 1848 when it was converted into the Prussian Province of Posen, by way of which it was transformed into one of Prussia's regional subdivisions, but still no part of the German Confederation.

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