Polish Corridor, strip of German territory awarded to newly independent Poland by the Treaty of Versailles in 1919. The strip, 20 to 70 mi (32–112 km) wide, gave Poland access to the Baltic Sea. It contained the lower course of the Vistula, except the area constituting the Free City of Danzig (see Gdańsk Gdańsk (gədänsk`), formerly Danzig
..... Click the link for more information. ) and the towns of Toruń, Grudziąz, and Bydogoszcz. Gdynia was developed as Poland's chief port and came to rival the port of Danzig. Free German transit was permitted across the corridor, which separated East Prussia from the rest of Germany. Although the territory had once formed part of Polish Pomerania Pomerania (pŏm'ərā`nēə)
..... Click the link for more information. , a large minority of the population was German-speaking. The arrangement caused chronic friction between Poland and Germany. In Mar., 1939, Germany demanded the cession of Danzig and the creation of an extraterritorial German corridor across the Polish Corridor. Poland rejected these demands and obtained a French and British guarantee against aggression. On Sept. 1, 1939, the Polish-German crisis culminated in the German invasion of Poland and World War II.

Polish Corridor

Strip of land that gave Poland access to the Baltic Sea. Transferred to the newly constituted state of Poland as part of the Treaty of Versailles (1919), the corridor, 20 to 70 mi (30 to 110 km) wide, separated eastern Prussia from the main part of Germany. The Germans resented the transfer, though the region had been historically Polish before the partitions of Poland and was inhabited by a Polish majority. When Poland refused to accede to Adolf Hitler's demands for extraterritorial highways across the corridor and cession of the free port city of Danzig (Gdansk), Germany seized the pretext to invade Poland (1939), beginning World War II.