The answer to this is the lesser houses of Men.Originally posted by Rhiannon
Topic: 'Who proved more detrimental to the good of the other peoples of Middle-Earth: The Noldorin Exiles or the lesser houses of Men?'
From Athrabeth Finrod ah Andreth:
So already before the Edain met the Eldar, there was grief among Men. Why is this?'Then are you content here?' said Finrod.
'Content?' said Andreth. No heart of Man is content. All passing and dying is a grief to it; but if the withering is less soon then that is some amendment, a little lifting of the Shadow.'
the answer can be found in The 'Tale of Adanel.' After Men had been deceived away from Eru, he came back and spoke to them one more time:
And Men grew afraid, but fearing their Master, still did his bidding. But:'Ye have abjured Me, but ye remain Mine. I gave you life. Now it shall be shortened, and each of you in a little while shall come to Me, to learn who is your Lord: the one ye worship, or I who made him.'
Does not this description fit others that we have heard of from the Silmarillion? Brodda the easterling, and Lorgan. Men, who were powerful and proud, and who enslaved other Men.For most of us, this was in vain. But to some he began to show favour: to the strongest and cruellest, and to those who went most often to the House. He gave gifts to them, and knowledge that they kept secret; and they became powerful and proud, and they enslaved us, so that we had no rest from labour amidst our afflictions.
And let us not forget Men like the sons of Ulfang, who at the turning point of the Nirnaeth Arnoediad
And so the eastern defences fell to the power of Morgoth.went over suddenly to Morgoth an drove in upon the rear of the Sons of Fëanor, and in the confusion that they wrought they came near to the standard of Maedhros. They reaped not the reward that Morgoth had promised them, for Maglor slew Uldor the accursed, the leader in treason, and the sons of Bór slew Ulfast and Ulwarth ere they themselves were slain. But new strength of evil Men came up that Uldor had summoned and kept hidden in the eastern hills, and the host of Maedhros was assailed now on three sides, and it broke, and was scattered, and fled this way and that.
And after this, Hithlum fell, and Doriath was ruined, and last of all fell Gondolin.Great was the triumph of Morgoth, and his design was accomplished in a manner after his own heart; for Men took the lives of Men, and betrayed the Eldar, and fear and hatred were aroused among those that should have been united against him. From that day the hearts of the Elves were estranged from Men, save only those of the Three houses of the Edain.
Men fought against Men, Dwarves, Elves and Men were alienated, against eachother. The only peoples who kept a firm alliance against Morgoth, were Elves and the Men of the Three Houses of the Edain. And from them came Eärendil, and the downfall of Morgoth.