Ile-de-France is a region of France. It includes the capital, Paris.
The name first appears in 1387, replacing the older "Pays de France" when the word pays began to mean nation rather than region. (source: Quid). It means, literally, "Isle of France": this is taken as meaning the inland peninsula delimited by the Oise[?], Seine, Ourcq[?] and Marne[?] rivers.