The etymology of Polesia (Полесье; Polesien), one of the largest forest and swamp areas on the continent, probably originates from the East Slavic root les 'forest', and the prefix po-, which in the meaning of 'on, by, along' is used to create place names.

The toponym was first mentioned in 1274 in the Galician–Volhynian Chronicle, when Prince Mstislav «...ѿ Копылѧ воюıа по Полѣсью...» ('was waging war in Polesia'). In Polish sources, the term polexiani is found, referring to one of the Sudovian tribes.

In 1650, the first known map of Polesia (the Paludum Polesiae Tabula of Daniel Zwicker) was published in Danzig. The borders of the region were designated differently, but in general it fit into the basin of the Pripyat River.
Martin Kromer localized Polesia as a land lying between Russia, Lithuania, Prussia, Volhynia and Masovia.

Image: Map of the Polesian Lowland by Daniel Zwicker (Paludum Polesiae Tabula). Willem Hondius, 1650.

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