Navy vet wakes up, speaks only Swedish

A fugue state, formally dissociative fugue or psychogenic fugue (DSM-IV Dissociative Disorders 300.13[1]), is a rare psychiatric disorder characterized by reversible amnesia for personal identity, including the memories, personality and other identifying characteristics of individuality. The state is usually short-lived (ranging from hours to days), but can last months or longer. Dissociative fugue usually involves unplanned travel or wandering, and is sometimes accompanied by the establishment of a new identity

en.wikipedia.org/wiki/Fugue_state