[Kuruharan]

This question also relates to the complimentary topics of the origins and nature of the orcs.

The first question to my mind seems to be if orcs were even capable of rationality or sentience without the guiding will of a Dark Lord. Even this question is ambiguous. The rout of the orcs, and the way it is described, on the face of it tend to say that orcs sink to the level of beasts and are no longer sentient without the will of their master. Eru's interactions with Aule with regard to the creation of the dwarves lend support to this theory. At least to some extent this passage indicates that something of the sort was part of Tolkien's thinking. However, during a long portion of the Second Age there was no active Dark Lord and yet orcs persisted.

It is also interesting to note that without the active engagement of a Dark Lord the orcs seem to be few and don't breed rapidly. Perhaps there is something of a socio-economic component to this. Do Dark Lords overpopulate their minions deliberately making them more aggressive in a competition for scarce resources whereas when orcs are left alone their population and aggression are low?

There is also leads to the question of what was the nature of a Dark Lord's control over his minions. They certainly appear to be rational actors in their own right. They are capable of sedition and acting against their master's interests. If a Dark Lord acted like an absolute puppet master one would think orcs would not be capable of acting this way. Did Morgoth literally split off thousands of pieces of his own "soul" and place them in his orcs and that is what animates them? It would explain many aspects of them...but then leaves us with the question of their despair and witlessness when their final Dark Lord was overthrown.

Let's assume for the following items that orcs are wholly rational actors.

For more bestial conceptions of orcs, like what has become the popular conception of them and to some extent Peter Jackson's version of them, it is hard to see how such creatures could have integrated into any society other than their own.

However, I don't think that Tolkien's conception of them was as bestial or grotesque as later ideas of orcs have come to make them. They bred "after the manner of the Children of Illuvatar" and Saruman, at least, successfully bred them with humans. Sauron might have as well. Orcs don't seem to have been a different species so much as a degraded version of elves or men. However, this is muddled by Tolkien's thoughts that orcs might be derived from animals in some way...although I'm not sure what animals could have been used to create such creatures.

Of course, this also even opens the door to questioning if Elves and Humans were really different "species" or just different types of the same "species."

So to finally get around to answering the question, I think orcs might be able to integrate into human society because they were more or less "human" to begin with.

Or perhaps not. It all depends on one's opinions on the exact nature of the orcs.

Or (to really get out into the weeds) there might be different orcish strains that might integrate better because of being more human but orcish strains that would not due to being more bestial in origin.