Here is a sampling from the David Gates review:
“While ‘The Kindly Ones’ may have a Nabokovian narrator — obscurantist in his erudition, hyperspecialized in his sexual tastes — its exhaustively researched historicity and documentarian realism clearly derive from “War and Peace.” It would take a writer of unimaginable genius to work these opposed tendencies into a coherent whole — and Tolstoy himself might have thought twice before trying to write fiction about the Holocaust. (Though, being Tolstoy, he would eventually have rolled up his sleeves anyhow.) Since nothing can rival the monstrosity of the historical record and the eyewitness accounts, the novelist may choose to put the focus on the individual, whose private concerns, however dire, will seem dinky in the context of what happened to six million individuals (not counting the always insufficiently anguished perpetrators). Or the novelist can try a knight’s move into the absurd — as Littell has done in episodes like the narrator’s odd encounter with Hitler — but it’s ultimately just an artful dodge. Absurdity may be disorienting, but brutality is absolute.
You can’t blame Littell for failing an impossible self-assignment. Nor can you fault a young novelist with a world of information, erudition and ambition for taking it on.”
Read the rest of the review.