The wizard and the eagle-lord appeared to know one another slightly, and even be on friendly terms. As a matter of fact Gandolf, who had often been in the mountains, had once rendered a service to the eagles and healed their lord from an arrow-wound.
...
The Lord of the Eagles would not take them anywhere near where men lived. "They would shoot at us with their great bows of yew," he said, "for they would think think we were after their sheep. and at other times they would be right. No! we are glad to cheat goblins of their sport, and glad to repay our thanks to you, but we will not risk ourselves for dwarves in the southward plains."
...
And so they parted. And though the lord of the eagles became in after days the King of All Birds and wore a golden crown, and his fifteen chieftains golden collars (made of the gold that the dwarves gave them), Bilbo never saw them again - except high and far off in the battle of Five Armies.
...
The Eagles had long had suspicion of the goblins' mustering; from their watchfulness the movements in the mountains could not be altogether hid. So they too gathered in great numbers, under the Great Eagle of the Misty Mountains; and at length smelling battle from afar they had come speeding down the gale in the nick of time.
...
"Where are the Eagles?" he asked Gandolf that evening, as he lay wrapped in many warm blankets.
"Some are on the hunt," said the wizard, "but most have gone back to their eyries. They would not stay here, and departed with the firts light of morning. Dain has crowned their chief with gold, and sworn friendship with them for ever."