Marie Curie was Polish.
Marie Skłodowska Curie ( [ ˈkjʊri , _ kjʊˈriː ] [ kyʁi ] ; [ kʲiˈri ] ; 7 November 18674 July 1934 ) , born Maria Salomea Skłodowska ( [ ˈmarja salɔˈmɛa skwɔˈdɔfska ] ) , was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity . She was born in Warsaw , in what was then the Kingdom of Poland , part of the Russian Empire . While a French citizen , Marie Skłodowska Curie ( she used both surnames ) never lost her sense of Polish identity .