Thorin Sends for Dain
After the death of Smaug, Thorin Oakenshield and his company of dwarves barricaded themselves inside the Lonely Mountain, only to find themselves besieged by a combined army of Wood-elves and Lake-men who demanded a share of the treasure. The dwarves were isolated, their supplies dwindling, and the winter weather closing in. It was in this desperate situation that Thorin turned to the one hope left to him: his kinsmen in the Iron Hills.
The Summons
Thorin's call for aid was delivered through the ancient raven Roäc, son of Carc, the chief of the great ravens of the Mountain. Roäc had brought the news of Smaug's death and the gathering of the elven and human armies. In response, Thorin burst forth in anger, declaring that none of his gold would be taken by thieves or the violent while he lived. He then commanded Roäc: "Bring us news of any that draw near. Also I would beg of you, if any of you are still young and strong of wing, that you would send messengers to our kin in the mountains of the North, both west from here and east, and tell them of our plight. But go specially to my cousin Dain in the Iron Hills, for he has many people well-armed, and dwells nearest to this place. Bid him hasten!" Roäc, though he would not say if the counsel was good or bad, agreed to do what could be done.
The Response
The ravens' swift flight carried the message across the desolate lands. Dain, Thorin's cousin and a lord of the dwarves of the Iron Hills, responded with immediate and formidable force. He gathered more than five hundred dwarves, each clad in a hauberk of steel mail that hung to his knees, with legs protected by a flexible metal mesh. They wielded heavy two-handed mattocks and carried short broad swords and round shields. Their beards were forked and plaited and thrust into their belts, and their caps and shoes were of iron. They marched with great speed, carrying huge packs of supplies on their backs in addition to their weapons, and arrived within two days' march of Dale, coming from the North-East. This rapid approach, unknown to the besieging army until the last moment, dramatically shifted the strategic situation, turning a static siege into a race against time and forcing Bard and the Elvenking to confront the possibility of a full-scale war.
Consequences
Dain's arrival precipitated the final crisis. When his vanguard appeared around the eastern spur of the Mountain, Bard refused to let them pass to the Gate, demanding the gold promised in exchange for the Arkenstone first. The dwarves of the Iron Hills, seeing the way barred, prepared to force their way through. The situation was on the verge of erupting into open battle between the dwarves and the combined forces of Elves and Men when a far greater threat emerged: the goblin army of Bolg, descending from the North. This common enemy forced a temporary alliance, and the Battle of Five Armies began. Thorin's decision to summon Dain, born of stubbornness and a refusal to negotiate, ultimately brought the very reinforcement that, when combined with the Elves and Men, was necessary to defeat the goblin horde, though it came at the cost of Thorin's own life and those of his nephews, Fili and Kili.
