I wanted to hold off posting until I could find the issue, but haven't had the time and I don't want to leave it out. But there's a Charlton science-fiction title with a story that basically copies Superman's origin but the entire civilization survives. They settle on a large continent on Earth, which (ahem) "explains" why the Chinese had better technology than the Europeans for centuries, and the evidence is, of course, in their slanted eyes that couldn't possibly have evolved on Earth.
Ohhhh...
(It's technically outside your scope, the Chinese in China not really being definable as a "minority," but I couldn't let that keep me from bringing it up.)