Map of ethnic Lithuanian territory ~100 years ago. See sources below

Vilnius is an intriguing case. While Russian and Polish officials recorded only ~2% of the city's inhabitants as Lithuanians, revisions by church authorities reveal that Lithuanians probably made up ~13% of Vilnius.

For the eastern Lithuanian lands, I employed the study by M. Grinblat (1959), marking in yellow the areas where tutejszy (lit. 'local') people lived. This population lacked a sense of national identity and could, under different circumstances, come out as Lithuanians, Poles or Belarusians. It turned out that today most of them consider themselves Polish.

This map is part of a larger project to map the interwar Lithuania that never achieved the borders it tried to. Lack of ethnic unity in the Vilnius are is one of the primary reasons why Lithuania did not control its capital between 1920 and 1939...