Early on in Game of Thrones, Jon Snow asks Samwell Tarly why his surname is Snow. “Because,” his loyal Wall companion slowly responds, “you’re a bastard from the North.” Jon Snow’s real name isn’t Jon Snow — it’s… well, that hasn’t been officially established yet. The closest we got to an answer came in the season six finale during the Tower of Joy flashback, where it’s confirmed that Rhaegar Targaryen (R) and Lyanna Stark (L) are Jon’s parents (J). Before she dies, Lyanna whispers something to her brother Ned, and although HBO intentionally didn’t provide closed captioning for the scene, a close, lip-reading inspection has some viewers believing “what she says is Jaehaerys.”
Who is Jaehaerys? As we wrote at the time:
Jaehaerys I Targaryen was the king of the Seven Kingdoms — the fourth Targaryen to hold such a title — approximately 200 years before the start of the series. He was dubbed “The Conciliator” or “The Wise.” A century and a half later, Jaehaerys II Targaryen became the 16th Targaryen to sit on the Iron Throne, and almost the last. That dishonor went to his son, Aerys II, better known as the Mad King, or Daenerys’ father. (Via)
Ned couldn’t name Lyanna’s son “Jaehaerys,” though, because that would give away his Targaryen bloodline, so he went with “Jon,” possibly in honor of his friend and Hand of the King predecessor, Jon Arryn. Or so the thinking goes. Again, nothing’s been established in the books or on the show, but the theory may have been confirmed in, all of places, Empire magazine.
As we saw in the last episode of season six, Bran’s (Isaac Hempstead Wright) psychic time-traveling “greensight” revealed the true nature of Jon’s birth heritage and his real name: Jaehaerys Targaryen. “Bran’s now in this precarious situation in which it’s just him and Meera [Ellie Kendrick], and he has all of this information that could change the entire story,” says Hempstead Wright. And it’s not just about Jon. “He knows about the origin of the White Walkers, too.”
Of course, this could just be Empire making a major assumption and not actual confirmation, but it’s a decent assumption to make. If you were a betting bastard, I’d put money on Jon’s name being Jaehaerys or Aegon, which is what I’m hoping for. It pairs extremely well with “…knows nothing.”