From their first unveiling in Parisian salons in the early 1910s, Giorgio de Chirico’s Metaphysical paintings (1909-1919) set off a discursive pursuit of their putative geographic origins. On the occasion of a 1927 exhibition, the prominent Parisian critic, Waldemar George, suggested a new rubric under which to file de Chirico’s images – a way, perhaps, to reconcile their irreducible incongruities into one fold: “réalisme méditerrané.” In the wake of widespread confirmation of his supposed Mediterraneanness, however, the artist himself insisted otherwise. What, then, prompted his umbrage at the notion of his art as quintessentially Mediterranean? It was, it seems, a particular kind of Mediterraneanism at which de Chirico took offense, and from which he sought – even in his earliest writings – to distinguish his own work. It was the work of Friedrich Nietzsche that arbitrated for de Chirico an authentic Mediterranean vision, one corrupted – or rather, uncorrupted – through its popularization as a benign cultural commonplace. By de Chirico’s consistent admission, it was Nietzsche’s work that led him to paint of certain architectural spaces a particular, Mediterranean “Stimmung.” In seeking to flesh out the precise origins and resonances of that ineffable category, I address how Nietzsche’s insistence upon the Mediterranean as a philosophical model – rather than a mere subject or site – influenced the development of de Chirico’s Metaphysical paintings, and his pursuit of a certain pre-Socratic primitivism.