Hopefully I'm not mangling the names/framework very much, but PKM gives the Celts a rather winnowed-out descent from an original group of space refugees from Numenore who settled on Earth and founded Atlantis. After Atlantis was destroyed, some of the survivors of *that* disaster relocated to the regions of Europe now considered Celtic; the ex-Atlanteans became known as the Tuatha de Danaan, the Sidhe, the Fair Folk etc. with eternal youth, indefinitely prolonged lifespans, superhuman powers, etc. Some of them intermarried with garden-variety humans.

Eventually, all of the Danaans and most of the Celts left Earth to get away from St. Patrick, and founded the space empire of Keltia. It looks as if her website's compendium is still (patchily?) archived here (http://web.archive.org/web/20020803160156/www.lizardqueen.com/html/keltcomp.html), though I haven't checked all of the links to see if they're still attached to anything.

Aha, her long essay about where/how she feels innocent fandom crosses the line is archived here (http://web.archive.org/web/20020619234644/www.lizardqueen.com/html/karma.html); likewise, her essay about Blackmantle is here (http://web.archive.org/web/20020204092343/www.lizardqueen.com/html/FAQ53.html). I've orphaned both of those links from their original framed FAQ menu, whose archive keeps acting funny at me.