Polish is a West Slavic language spoken in Poland. It is the most widely spoken West Slavic language.
To read more about Polish, please see Wikipedia.
Uralic Natlangs: Finnish * Khanty * Mansi * Mordvinic * Proto-Uralic
Altaic (controversial): Japanese
Uto-Aztecan Natlangs: Nahuatl
Isolate Natlangs: Basque * *
Hypothetical/debated Natlangs and Natlang families: Danubian * Europic (obsolete)