The Fate of.....

[Morthoron]

Originally Posted by Urwen

What happens to the individuals who defy orders or are responsible for some great tragedy after they die? Do they get re-embodied?

This would not concern mortals, as there is no evidence they are re-embodied at all; in fact, they are set apart in Mandos and none know their fate. As for Elves, there is no evidence whatsoever that Elves who have committed evil, like Maeglin, are allowed to return from Mandos as a corporeal manifestation. That is solely in the realm of Mandos as the final arbiter of such a reincarnation. Not even Feanor is allowed to return until the very end of times.

As for Maiar? Saruman, once he died at the hands of Wormtongue, was not even allowed to return to Valinor. His spirit as Shippey notes, "dissolved into nothing". But Tolkien seemed more specific than that: "Whereas Curunir was cast down, and utterly humbled, and perished at last by the hand of an oppressed slave; and his spirit went whithersoever it was doomed to go, and to Middle-earth, whether naked or embodied, came never back."

Sauron, too, was not allowed to reincarnate after the destruction of the One Ring. His spirit rose above Mordor, "a huge shape of shadow, impenetrable, lightning-crowned, ...terrible but impotent," only to be blown away by a great wind. Tolkien notes in Letter 200: "The impossibility of re-building after the destruction of the Ring, is sufficiently clear ‘mythologically’ in the present book."

Interesting that both the spirits of Sauron and Saruman were blown away by the wind. Although the direction of the wind is not implied as it blew away Sauron's spirit, it is very specific in the case of Saruman's spirit as it loomed above the Hobbits: "For a moment it wavered, looking to the West; but out of the West came a cold wind, and it bent away, and with sigh dissolved to nothing." The implication is that it was blown away from the Blessed Realm.

But back to your original query, Tolkien is quite specific about "wicked" spirits and fea:

"If they do not sink below a certain level. Since no fea can be annihilated, reduced to zero or not-existing, it is no[t] clear what is meant. Thus Sauron was said to have fallen below the point of ever recovering, though he had previously recovered. What is probably meant is that a "wicked" spirit becomes fixed in a certain desire or ambition, and if it cannot repent then this desire becomes virtually its whole being. But the desire may be wholly beyond the weakness it has fallen to, and it will then be unable to withdraw its attention from the unobtainable desire, even to attend to itself. It will then remain for ever in impotent desire or memory of desire."

JRRT, text VII, Myths Transformed, Morgoth's Ring

So, no, Maeglin ain't coming back, particularly since he didn't seem to have any redeeming qualities or the ability to repent. He was the very embodiment of what Tolkien referred to as "fixed in a certain desire or ambition, and if it cannot repent then this desire becomes virtually its whole being."