First introduced in A Game of Thrones, the three-eyed crow has been a mysterious figure who opened Bran’s “third eye” to magic, and began him on a path that has led him from Winterfell to the lands beyond the Wall. When we are finally introduced to him, the first and most surprising thing we learn about him is the fact that he is not a child of the forest. Instead, this “pale lord in ebony finery” is a man, ancient and wizened, more a corpse than a live. Bound to a great weirwood, its roots having worked its way into and even through his body, he has waited for many years for Bran—or someone like Bran—to come, to save the world of men from the coming threat.
For those who’ve not read the Dunk & Egg stories, the answer as to who this may be may be mystifying. He reveals that he was once a brother of the Watch, that he had a brother he loved and one he despised, and—most importantly—that his name was Brynden, and that Bran’s great-uncle Brynden Tully may well have been named for him. Putting this all together, there’s a hint in A Feast for Crows as to who this is—a companion to Maester Aemon, when he first came to Wall, recently freed from the dungeons by King Aegon V the Unlikely to be able to take the black, and eventually rising to become Lord Commander of the Night’s Watch:
Brynden Rivers, known as Bloodraven, one of the Great Bastards of King Aegon IV the Unworthy. Born an albino and with a large red birthmark on his cheek that was immediately compared to the raven of his mother’s house of Blackwood, he grew to become one of the most feared figures in the Seven Kingdoms, helping to bring down the first Blackfyre Rebellion (and allegedly personally killing his brother, Daemon Blackfyre, as well as his sons), supposedly practicing sorcery, and becoming a feared master of spies who became Hand of the King and was said to command “a thousand eyes and one” (referring to his having only a single eye, having lost the other on the Redgrass Field to his half-brother Bittersteel. Many of the details of this splendid figure—Martin’s nod, in some ways, to Elric of Melnibone—have appeared in the “Dunk and Egg” novels, set almost a hundred years prior to the novels when Brynden was approaching the height of his power and influence, but Martin also provided some key details in a letter to Amok.
The story of how he came to leave his post as Lord Commander and find his way to the secret cavern of the children of the forest is one that hasn’t yet been told.