Where does “Polonia” come from?

Polonia (Sardinian) comes from Medieval Latin Polonia, from Polish Polanie, from Proto-Slavic poľane, from Proto-Slavic poľe, from Proto-Indo-European pleh₂- — flat.

Ancestry of “Polonia”, step by step

StepLanguageWordMeaning
1Medieval LatinPoloniaPoland
2PolishPolaniePoles; field-dwellers
3Proto-Slavicpoľane—
4Proto-Slavicpoľefield
5Proto-Indo-Europeanpleh₂-flat
Every word from Proto-Indo-European pleh₂- →Every word from Proto-Slavic poľe →Every word from Proto-Slavic poľane →