Kreis Birnbaum

The Kreis Birnbaum (Polish: Powiat międzychodzki) was an administrative district in Prussia (Kreis) in the west of the Grand Duchy of Posen and the succeeding Province of Posen, part of Regierungsbezirk Posen between 1815 and 1920. Today the area belongs to the Polish voivodeships of Greater Poland and Lubusz.

The lands around the Greater Polish town of Międzychód had been part of the Poznań Voivodeship since the 14th century, they were annexed by the Kingdom of Prussia during the Second Partition of Poland in 1793. Part of the Napoleonic Duchy of Warsaw from 1807, they again fell to Prussia according to the 1815 Congress of Vienna. The district's borders were finally determined by resolution of 1818. The administrative seat from 1833 was at Sieraków (Zirke), from 1867 in Międzychód (Birnbaum).

With the Province of Posen, Kreis Birnbaum became part of the German Empire in 1871. With effect of 1 October 1887, its westernmost part, including Skwierzyna (Schwerin an der Warthe) and Bledzew (Blesen) was split off as Kreis Schwerin in Posen. In the aftermath of the German defeat in World War I, a Greater Polish Uprising broke out in December 1918, which brought most of the Province of Posen under Polish control. According to the Treaty of Versailles, the German Weimar Republic had to cede most of the province, including Kreis Birnbaum, to Poland. The handover was executed by between 17 January and 4 February 1920.

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