'House of the Dragon' Premiere Changes Context of Major 'Game of Thrones' Plot Point

The most significant sequence in the premiere episode of "House of the Dragon" alters the story of "Game of Thrones."

In the final minutes, King Viserys I Targaryen tells Rhaenyra, his new-found heir, that Aegon the Conqueror, the first Targaryen king of Westeros, foreshadowed the eventual Battle of Winterfell 100 years ago. For reference, the battle takes place during the events of "Thrones," 200 years after "Dragon."

Before we delve into the significance, here's the scene:

The conversation reveals that Aegon's prophetic dream led him to conquer Westeros not for self-fulfilling power but to protect the Seven Kingdoms during an eventual war with the White Walkers. Because Aegon would never live to see the battle, he began a tradition that passes the secret down to each Targaryen heir.

The tradition says to not alert the rest of Westeros until it's time to rally the Seven Kingdoms against the White Walkers.

George R.R. Martin, the author of the show's source material, confirmed that a prophecy died in secret with Rhaegar Targaryen, Daenerys' brother and Jon Snow's father, ahead of the premiere.

"It’s mentioned here and there—in connection with Prince Rhaegar," Martin said of the prophecy we now know.

This confirms a long-lasting fan theory that Rhaegar knew of the White Walkers' existence before his death.

The story goes that Rhaegar went into a historical library uninterested in battle but came out deciding he needed to be a soldier. Learning of the threat beyond the Wall would certainly make one change their tone on combat. 

In "Game of Thrones," the story is that only the Night's Watch was aware the snowy creatures were more folklore.

However, Rhaegar ran off with Lyanna Stark, Jon Snow's mother, provoking Robert's Rebellion, in which Rhaegar and the Targaryen reign fell.

Much of the deadly events in "Thrones" would have been avoided had a King warned there were bigger problems ahead. Rhaegar's involvement with Lyanna is the catalyst to not only Robert's ascension, but also Joffrey's, Cersei's, and Bran's.

One might wonder why such a consequential detail would not make it into the series affected by the tale. Well, Martin's inability to finish his novels is to blame.

Showrunner Ryan Condal confirms this scene came at the behest of Martin: “A lot of them said I committed A Song of Ice and Fire heresy, but I did tell them: ‘That came from George.’ I reassured everybody.”

Had Martin finished his final two novels in time for the HBO series to adapt, as he promised, this detail would have been included in "Game of Thrones."

With waning hope that he'll finish the novels, Martin may have to tell the tale through the lens of a prequel series unaffected by Rhaegar.