Meaning: old Norse 'obstinate'
Dates: 2644 - 2850 III
Children: Thorin II, Frerin, Dís
From the sack and the burning [of Erebor] many of Thrór's kin escaped; and last of all from the halls by a secret door came Thrór himself and his son Thráin II. They went away south with their family into long and homeless wandering. With them went also a small company of their kinsmen and faithful followers.
Years afterwards Thrór, now old, poor, and desperate, gave to his son Thráin the one great treasure he still possessed, the last of the Seven Rings, and then he went away with one old companion only, called Nár. Of the Ring he said to Thráin at their parting:
'This may prove the foundation of new fortune for you yet, though that seems unlikely. But it needs gold to breed gold.'
'Surely you do not think of returning to Erebor?' said Thráin.
'Not at my age,' said Thrór. 'Our vengeance on Smaug I bequeath to you and your sons. But I am tired of poverty and the scorn of Men. I go to see what I can find.' He did not say where
[word reached Thráin of Thrór's murder by Azog in Moria] ...when he had wept and torn his beard he fell silent. Seven days he sat and said no word. Then he stood up and said: 'This cannot be borne!' That was the beginning of the War of the Dwarves and the Orcs, which was long and deadly, and fought for the most part in deep places beneath the earth.
Thráin at once sent messengers bearing the tale, north, east, and west; but it was three years before the Dwarves had mustered their strength. Durin's Folk gathered all their host, and they were joined by great forces sent from the Houses of other Fathers; for this dishonour to the heir of the Eldest of their race filled them with wrath. When all was ready they assailed and sacked one by one all the strongholds of the Orcs that they could from Gundabad to the Gladden. Both sides were pitiless, and there was death and cruel deeds by dark and by light. But the Dwarves had the victory through their strength, and their matchless weapons, and the fire of their anger, as they hunted for Azog in every den under mountain.
At last all the Orcs that fled before them were gathered in Moria, and the Dwarf-host in pursuit came to Azanulbizar. That was a great vale that lay between the arms of the mountains about the lake of Kheled-zâram and had been of old part of the kingdom of Khazad-dûm. When the Dwarves saw the gate of their ancient mansions upon the hill-side they sent up a great shout like thunder in the valley. But a great host of foes was arrayed on the slopes above them, and out of the gates poured a multitude of Orcs that had been held back by Azog for the last need.
At first fortune was against the Dwarves; for it was a dark day of winter without sun, and the Orcs did not waver, and they outnumbered their enemies, and had the higher ground. So began the Battle of Azanulbizar (or Nanduhirion in the Elvish tongue), at the memory of which the Orcs still shudder and the Dwarves weep. The first assault of the vanguard led by Thráin was thrown back with loss, and Thráin was driven into a wood of great trees that then still grew not far from Kheled-zâram. There Frerin his son fell, and Fundin his kinsman, and many others, and both Thráin and Thorin were wounded.
When at last the battle was won the Dwarves that were left gathered in Azanulbizar. They took the head of Azog and thrust into its mouth the purse of small money, and then they set it on a stake. But no feast nor song was there that night; for their dead were beyond the count of grief. Barely half of their number, it is said, could still stand or had hope of healing.
None the less in the morning Thráin stood before them. He bad one eye blinded beyond cure, and he was halt with a leg-wound; but he said: 'Good! We have the victory. Khazad-dûm is ours! '
But they answered: 'Durin's Heir you may be, but even with one eye you should see clearer. We fought this war for vengeance, and vengeance we have taken. But it is not sweet. If this is victory, then our hands are too small to hold it.'
And those who were not of Durin's Folk said also: 'Khazad-dûm was not our Fathers' house. What is it to us, unless a hope of treasure? But now, if we must go without the rewards and the weregilds that are owed to us, the sooner we return to our own lands the better pleased we shall be.'
Then Thráin turned to Dáin, and said: 'But surely my own kin will not desert me?'
'No,' said Dáin. 'You are the father of our Folk, and we have bled for you, and will again. But we will not enter Khazad-dûm. You will not enter Khazad-dûm. Only I have looked through the shadow of the Gate. Beyond the shadow it waits for you still: Durin's Bane. The world must change and some other power than ours must come before Durin's Folk walk again in Moria.'
So Thráin and Thorin with what remained of their following (among whom were Balin and Glóin) returned to Dunland, and soon afterwards they removed and wandered in Eriador, until at last they made a home in exile in the east of the Ered Luin beyond the Lune. Of iron were most of the things that they forged in those days, but they prospered after a fashion, and their numbers slowly increased. But, as Thrór had said, the Ring needed gold to breed gold, and of that or any other precious metal they had little or none.
It was therefore perhaps partly by the malice of the Ring that Thráin after same years became restless and discontented. The lust for gold was ever in his mind. At last, when he could endure it no longer, he turned his thoughts to Erebor, and resolved to go back there. He said nothing to Thorin of what was in his heart; but with Balin and Dwalin and a few others, he arose and said farewell and departed.
Little is known of what happened to him afterwards. It would now seem that as soon as he was abroad with few companions he was hunted by the emissaries of Sauron. Wolves pursued him, Orcs waylaid him, evil birds shadowed his path, and the more he strove to go north the more misfortunes opposed him. There came a dark night when he and his companions were wandering in the land beyond Anduin, and they were driven by a black rain to take shelter under the eaves of Mirkwood. In the morning he was gone from the camp, and his companions called him in vain. They searched for him many days, until at last giving up hope they departed and came at length back to Thorin. Only long after was it learned that Thráin had been taken alive and brought to the pits of Dol Guldur. There he was tormented and the Ring taken from him, and them at last he died.
-Durin's Folk, Appendix A, The Return of the King
Kitt of Lindon 1.31.05.