As some of you probably know, Mighty Mouse was originally known as Super Mouse, an out and out parody of Superman. Nearly a decade after his debut the "Mouse of Tomorrow" gets an origin----sort of.
In 1951's "The Cat's Tale", we find that a witch (we only see a green-skinned hand) leaves the future hero with a kindly mouse couple living in a tree. A cat, scared to the point where he's dragging on three cigarettes at once, tells this odd tale. The origin, again, suggests a send-up of Superman.