Beethoven’s "Fifth Symphony" is in C minor but the last movement is in the major. This is not a Tierce de Picardie in this case, as the term applies only when just the last chord alters. The term was introduced in 1767 by Rousseau in his "Dictionnaire de musique" (Dictionary of Music). “Tierce” means “third”, but no one knows why he called it “Picardie” (Picardy is an area in the north of France).