I wonder if you might have seen this essay by David Brin...

Now ponder something that comes through even the party-line demonization of a crushed enemy -- this clear-cut and undeniable fact: Sauron's army was the one that included every species and race on Middle Earth, including all the despised colors of humanity, and all the lower classes.

Hmm. Did they all leave their homes and march to war thinking, "Oh, goody, let's go serve an evil Dark Lord"?

Or might they instead have thought they were the "good guys," with a justifiable grievance worth fighting for, rebelling against an ancient, rigid, pyramid-shaped, feudal hierarchy topped by invader-alien elfs and their Numenorean-colonialist human lackeys?

Picture, for a moment, Sauron the Eternal Rebel, relentlessly maligned by the victors of the War of the Ring -- the royalists who control the bards and scribes (and moviemakers). Sauron, champion of the common Middle Earthling! Vanquished but still revered by the innumerable poor and oppressed who sit in their squalid huts, wary of the royal secret police with their magical spy-eyes, yet continuing to whisper stories, secretly dreaming and hoping that someday he will return ... bringing more rings.