Pretty much, although the language lasted a little while into the 20th.Occidental and Occitan France are two different concepts and overlapping geographical regions. Occidental means western France, so Occidental France is modern France minus Burgundy and Provence. Occitan France is the part of France where people speak Lenga d'òc (a language most closely related to Catalan and Piedmontese) which used to be most of southern France.
EDIT: And as far as I recall Occitan culture was destroyed with the advent of public schools in the late 19th century.