Yes, Tolkien was an extremely devoted Catholic. Yes he was just as much devoted to Nordic Lore. But in the end, he was his own man and he reubuked both traditions in a profound but hidden moment within "Lord of the Rings".
Let me tell the story;
Remember when just before the battle for Gondor, Aragorn is advised to enter the Mountain and rally the Oath-breaking Dead around his sword? Naturally, he's troubled. Why would he want to rely on liars, murderers, thieves and oath-breakers to win his kingdom? But he goes into the Mountain and he rallies them anyway... THEN, we see him arrive at the battle of Gondor in a SHIP. (Remember the ship.)
To understand what all of this really means, we also have to look at how it happens in its parallel story to be found in Norse mythology. The souls of liars, murderers, thieves and oath-breakers are all sent to Hel or Niflheim. It's reported to be a cold, dark after-life, where people suffer starvation and thirst.
Loki, the Trickster of Norse Mythology, rebels against the gods (Aesir & Vanyir) and decides to take all power for himself. The only for him to do this is to kill all the gods. So, Loki commandeers a ship and goes and rallies these condemned souls to fight for him against the Aesir & Vanyir. This is Ragnarok, the Battle to end all Battles, the Doomsday Battle that will bring the end of the world. And in the end, all these souls die a second death...
Tolkien was a man who was deeply, deeply committed to the ideas of; innate value of life, repentance and redemption (not to be confused with the Christian idea of "Salvation"). Witness his treatment of Gollum... And more importantly, witness his treatment of the Oath-breaking Dead from the Mountain. Instead of sending the Oath-breaking Dead to an eternal, fiery Christian Hell... Instead of sending them the evil Loki who would only lead them into death and destruction at the hands of the Aesir and Vanyir... Tolkien sent the Oath-breaking Dead a Redeeming King in Aragorn, he sent them a 2nd chance to redeem themselves through noble action, a 2nd chance to free their own souls. Tolkien sent them a chance to live.
When I saw it in the movie theater, I confess, I wept.
