Helen, I think you're right on the definition of "challenged."

Fishlet, Lady Chatterly's Lover *was banned in the US, when it first came out (late 20s?). My grandmother had a copy "smuggled" to her by a Brit friend who came to visit a few years later (either the ban was lifted first in the UK or else she had a bootleg copy...). The ALA list doesn't go back more than a couple of decades, far as I can tell.