The Free City of Danzig is established.
The Free City of Danzig (German: Freie Stadt Danzig; Polish: Wolne Miasto Gdańsk; Kashubian: Wòlny Gard Gduńsk) was a semi-autonomous city-state that existed between 1920 and 1939, consisting of the Baltic Sea port of Danzig (now Gdańsk, Poland) and nearly 200 towns and villages in the surrounding areas. It was created on 15 November 1920 in accordance with the terms of Article 100 (Section XI of Part III) of the 1919 Treaty of Versailles after the end of World War I.
The Free City included the city of Danzig and other nearby towns, villages, and settlements that were primarily inhabited by Germans. As the treaty stated, the region was to remain separated from the post-war German Republic and from the newly independent Polish Republic. The Free City was under League of Nations protection and put into a binding customs union with Poland.
Poland was given certain rights pertaining to communication, the railways and port facilities in the city. The Free City was created in order to give Poland access to a sizeable seaport. In 1938, the Free City's population of 410,000 was 98% German, 1% Polish and 1% other. In the 1920 Constituent Assembly election, the Polish Party received over 6% of the vote, but its percentage of votes later declined to about 3%.
In 1921, Poland began to develop the city of Gdynia, then a midsized fishing town. This completely new port north of Danzig was established on territory awarded in 1919, the so-called Polish Corridor. By 1933, the commerce passing through Gdynia exceeded that of Danzig. Notwithstanding this, Poland refused to relinquish trading and other rights awarded to it, further alienating the Danzigers.
By 1936, the city's senate had a majority of local Nazis, and agitation to rejoin Germany was stepped up. Many Jews fled from German antisemitism, persecution, and oppression. After the German invasion of Poland in 1939, the Nazis abolished the Free City and incorporated the area into the newly formed Reichsgau of Danzig-West Prussia. The Nazis classified the Poles and Jews living in the city as subhumans, subjecting them to discrimination, forced labor, and extermination. Many were murdered at Nazi concentration camps, including nearby Stutthof (now Sztutowo, Poland).During the city's conquest by the Soviet Army in the early months of 1945, a substantial number of citizens fled or were killed. In 1945, the city officially became part of Poland in accordance with the Potsdam Agreement. In the period immediately after the war, many surviving Germans were expelled to West or East Germany, while members of the pre-war Polish ethnic minority started returning and new Polish settlers began to come. Gdańsk suffered severe underpopulation from these events and did not recover until the late 1950s.