** Possible Spoilers **
Empire magazine recently published a quote from Isaac Hempstead Wright (Bran Stark) about how his character holds a key information about Jon Snow’s parentage and also revealed Jon Snow’s real name: Jaehaerys Targaryen. Check out the article from the magazine below.
This makes Jon Snow Jaehaerys III. First Jaehaerys was the fourth Targaryen King to sit on the iron throne while Jaehaerys II Targaryen was the sixteenth. Jaehaerys II was also the father of Mad King Aerys II Targaryen and grandfather of Rhaegar Targaryen, Jon Snow’s real father. He reigned for only 3 years but was a very capable and wise king, who ended the Blackfyre threat, reconciled many great houses and therefore restored order to the Kingdom.