- Beorn is met in The Hobbit. He was a skin-changer: a gigantic man who had the ability to change into a great black bear. He lived East of the Misty Mountains, in a house surrounded by flowers and friendly animals. He could talk to animals and they helped him whenever they could. He was a friend of the Radagast the Brown, and helped Gandalf and his companions on their journey to the dragon Smaug.
- In the Hobbit, Beorn makes a decisive appearence in the "Battle of the Five Armies." ( T.A. 2941)
- "... Beorn himself arrived at the battle, apparently having heard news that a large army of Goblins was on the move. This time he did not appear in his former shape of a large Man, but had changed his skin to that of a huge bear. Beorn drove through the Goblin lines, but paused to carry the wounded Thorin out of the battle with his paw. Beorn then returned to the battle, his wrath redoubled, and smashed the ranks of the bodyguard of Bolg, pulling down that great goblin and crushing him in ruin before the Goblin horde. The Goblins then panicked and scattered, to be picked off by hunting forces from the victors."
- In naming his character, Tolkien used beorn, an Old English word for bear, which later came to mean man and warrior (with implications of freeman and nobleman in Anglo-Saxon society). It is related to the Scandinavian names Björn (Swedish and Icelandic) and Bjørn (Norwegian and Danish), meaning bear. The word baron is indirectly related to beorn. 
- "He is a skin-changer. He changes his skin; sometimes he is a huge black bear, sometimes he is a great strong black-haired man with huge arms and a great beard. I cannot tell you much more, though that ought to be enough. Some say that he is a bear descended from the great and ancient bears of the mountains that lived there before the giants came. Others say that he is a man descended from the first men who lived before Smaug or the other dragons came into this part of the world, and before the goblins came into the hills out of the North. I cannot say, though I fancy the last is the true tale."