Polish–Lithuanian relations during World War II

The issue of Polish and Lithuanian relations during World War II is a controversial one, and some modern Lithuanian and Polish historians still differ in their interpretations of the related events, many of which are related to the Lithuanian collaboration with Nazi Germany and the operations of Polish resistance organization of Armia Krajowa on territories inhabited by Lithuanians and Poles. In recent years a number of common academic conferences have started to bridge the gap between Lithuanian and Polish interpretations, but significant differences still remain.

Polish–Lithuanian relations were strained during the interwar period, mostly due to the conflict over the Vilnius (Wilno) Region (which had a Polish majority but was seen by Lithuanians as their historical capital). This conflict resulted in enmity within local communities and the mutual harsh treatment of the Polish and Lithuanian ethnic minorities living in both countries. The tensions had begun to diminish by early spring of 1938 (see 1938 Polish ultimatum to Lithuania), when both nations restored normal relations, and telephone, mail, rail, and road communications were established. The re-approachment was however stopped when Germany and Soviet Union invaded Poland in September 1939. Lithuania remained independent at the beginning of World War II, however it was soon occupied by the Soviet Union, then by Germany and then again by the Soviet Union, which had earlier annexed it as one of its republics.

The Vilnius Region had a mixed population of often-conflicted Polish, Jewish, Belarusian and Lithuanian communities. This was further aggravated by Germans forcibly relocating Lithuanian families to the region from western parts of Lithuania. During the war these conflicts resulted in thousands of deaths, as groups on both sides used the opportunities offered by the war to commit violent acts against those they perceived as enemies.

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