The Marienwerder Region (Regierungsbezirk Marienwerder) was a government region (Regierungsbezirk), of Prussia from 1815 until 1945. The regional capital was Marienwerder in West Prussia (now Kwidzyn). The Marienwerder Region was part of the Province of West Prussia from 1815-1829, and again 1878-1920, belonging to the Province of Prussia in the intervening years. The Marienwerder Region was then placed under an inter-Allied commission from 1920-1922 and was eventually divided, with the western districts included within the newly established Polish Republic as part of the so-called Polish Corridor. The eastern part of Marienwerder that voted to be incorporated within the Weimar Republic was named the Region of West Prussia (Regierungsbezirk Westpreußen) while it was joined to the Province of East Prussia from 1922 to 1939, after which its original name was restored until its dissolution in 1945.
Most of Polish Royal Prussia was annexed by King Frederick the Great of Prussia in the 1772 First Partition of Poland. The town of Marienwerder, previously in Ducal Prussia, became an administrative capital of the newly acquired territory, which became the Province of West Prussia on 31 January 1773.
West Prussia was divided into the regions of Danzig and Marienwerder in 1815, following the Napoleonic Wars. While the governor and provincial authorities were based in Danzig (Gda?sk), the provincial supreme court of Marienwerder (1772-1943) was in the homonymous town.
From 1815-18, West Prussia was reorganised into districts (or Kreise), within each government region. The Marienwerder Region included the rural districts (Kreise) of Culm (1818-1920), Briesen (1887-1920), Deutsch-Krone (1772-1945), Flatow (1818-1945), Graudenz-Land (1818-1920), Konitz (1772-1920), Löbau in West Prussia (1818-1920), Marienwerder (1752-1945), Rosenberg in West Prussia (1818-1945), Schlochau (1818-1945), Schwetz (1818-1920), Strasburg in West Prussia (1818-1920), Stuhm (1818-1945), Thorn-Land (1818-1920), and Tuchel (1875-1920).
As a result of the Treaty of Versailles following World War I, most of West Prussia, including much of the Marienwerder Region, was allocated to the Second Polish Republic. Parts of the territory east of the river Vistula took part in the East Prussian plebiscite and remained in the Free State of Prussia within Weimar Germany. These parts of the Marienwerder Region were officially incorporated into the Province of East Prussia in 1922, and renamed from Marienwerder Region to Region of West Prussia. This smaller region consisted of the rural districts of Elbing-Land, Marienburg in West Prussia, Marienwerder, Rosenberg in West Prussia, Stuhm, and the city of Elbing (Elbl?g); the districts of Elbing and Marienburg and the city of Elbing had previously been part of the Danzig Region. The districts of Deutsch-Krone, Flatow, and Schlochau became part of the new Prussian Frontier March of Posen-West Prussia. The districts of Graudenz, Konitz, Culm, Löbau, Schwetz, Strasburg in West Prussia, and Thorn became part of the Pomeranian Voivodeship of Poland.
On 26 October 1939, following the Wehrmacht's conquest of the Polish Corridor at the beginning of World War II, the Region of West Prussia was transferred from East Prussia to the newly created Reichsgau Danzig-West Prussia. It was also given back its original name of Marienwerder Region and included besides of German districts also occupational district authorities on Polish territory.
The Marienwerder Region was dissolved in 1945 following Nazi Germany's defeat in the war. The Soviet conquerors handed the region's territory to Poland in March 1945. Since that time it has been part of Poland. At the Potsdam Conference, the three Allies assigned the region to Polish administration in August 1945, and the German-Polish Border Treaty confirmed the annexation in 1990.
Regierungsbezirk Marienwerder had a majority German speaking population, with a large Polish speaking minority.
1 includes Kashubian speakers
Districts in the Region of West Prussia, based in Marienwerder, as of 31 December 1937
Each of the nineteen Regierungsbezirke featured a non-legislative governing body called a Regierungspräsidium or Bezirksregierung (regional government) headed by a Regierungspräsident (regional president), concerned mostly with applying state law to administrative decisions on municipalities within their jurisdiction and their umbrella organisations (the districts).