Romanian Bridgehead

The Romanian Bridgehead (Polish: Przedmoście rumuńskie) was an area in southeastern Poland, now located in Ukraine. During the Invasion of Poland of 1939 (at the start of World War II), on 14 September the Polish commander-in-chief Marshal of Poland Edward Rydz-Śmigły ordered all Polish troops fighting east of the Vistula (approximately 20 divisions still retaining cohesion) to withdraw towards Lwów, and then to the hills along the borders with Romania and the Soviet Union.

The plan was a fall back plan in case it was impossible to defend the Polish borders, and assumed that the Polish forces would be able to retreat to the area, organise a successful defence until the winter, and hold out until the promised French offensive on the Western Front started. Rydz-Śmigły predicted that the rough terrain, the Stryj and Dniestr rivers, valleys, hills and swamps would provide natural lines of defence against the German advance. The area was also home to many ammunition dumps that were prepared for the third wave of Polish troops, and was linked to the Romanian port of Constanța, which could be used to resupply the Polish troops.

This plan is one of the reasons the Polish-Romanian Alliance was not activated by Poland. Poland and Romania had been allied since 1921 and the defensive pact was still valid in 1939. However, the Polish government decided that it would be much more helpful to have a safe haven in Romania and a safe port of Constanța that could accept as many Allied merchant ships as required to keep Poland fighting. The Polish Navy and merchant marine were mostly evacuated prior to 1 September (see Peking Plan); they were to operate from French and British ports and deliver the supplies through Romania.

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Wikipedia