'Game of Thrones' Drops a Huge Jon Snow Revelation That Changes Everything—Here's What It Means

This story contains spoilers about "Eastwatch," the latest episode of Game of Thrones, If you don't want plotlines spoiled, click away now.

Jon Snow is no bastard after all.

Sunday's Game of Thrones innocuously inserted a huge revelation during an off-the-cuff exchange between Gilly (Hannah Murray) and Samwell Tarly (John Bradley) that pretty much changes everything we know about Jon Snow, played by Kit Harington.

In Season 7, Episode 5, "Eastwatch," Gilly is seen reading through the notes of the long-deceased High Septon Maynard in the Citadel. Sam, meanwhile, is too preoccupied with self-pity to take note when Gilly asks him what annulment means and then says: "Maynard says here that he issued an annulment for a 'Prince Ragger' and remarried him to someone else at the same time in a secret ceremony in Dorne."

To unpack that: "Prince Ragger" is Prince Rhaegar Targaryen, the eldest son of the Mad King Aerys, and Daenerys Targaryen's brother. He was married to Elia Martell of Dorne, who was the sister of Prince Oberyn, seen in Season 4.

Game of Thrones 7x05—"Eastwatch"
Gilly and Sam find out something big about Jon Snow. Helen Sloan/HBO

As we discovered in Season 6's Tower of Joy flashback scene, Lyanna Stark—Ned Stark's sister—had an illegitimate child with Rhaegar, who seemingly abducted her, leading to the civil war known as Robert's Rebellion that resulted in the overthrow of the Mad King and the end of the Targaryen dynasty.

This big reveal in Episode 5 confirms two things: Not only is Jon Snow, as we have always believed, not a bastard, he's also the rightful heir to the Iron Throne.

Here is everything you need to know about the big reveal:

The story of R + L = J

In the Game of Thrones story, viewers and characters have always been led to believe that, in events predating the start of the series, Rhaegar was infatuated with Lyanna, kidnapped her, held her hostage and raped her. This led to Lyanna's betrothed, Robert Baratheon, going to war with the Mad King and eventually killing Rhaegar. (Rhaegar's wife, Elia, and their two children Rhaenys and Aegon, were killed by Lannister soldier Gregor Clegane, aka the Mountain—hence why Oberyn wanted to fight him in Season 4.)

That is the official version of events, anyway. When Sansa Stark recounted this version to Littlefinger in Season 5, his facial expression suggested he knew otherwise:

That Rhaegar kidnapped and raped Lyanna may have been a skewed version of events, it seems. In reality, they were in love and ran away together. As we found out in "Eastwatch," they ran away and got married after Rhaegar annulled his marriage to Elia.

Sometime before their marriage or after, Lyanna fell pregnant with Jon Snow. In the Season 6 Tower of Joy flashback scene, a young Ned Stark arrived at the Tower—which is in Dorne—and found his sister, Lyanna, in the middle of childbirth. Lyanna was aware she was going to die from complications in labor and made Ned make a promise, saying: "If Robert finds out, he'll [kill him]...you know he will. You have to protect him." The promise is presumably that Ned look after her son, and as we know, Ned raised Jon as his own bastard son, even though it meant royally pissing off his wife, Catelyn.

Related: Melisandre's Varys prophecy, explained

The royal line of succession

Jon Snow is the true King of the Andals and the First Men and Lord of the Seven Kingdoms.

The revelation that Jon's parents married changes the course of the show—because in GoT lore, bastards have no inheritance claim. Even if his dad, Prince Rhaegar, was the crown prince to the Iron Throne, he wouldn't have had any claim to it if Rhaegar and Lyanna hadn't married.

But they did. Which means that per GoT's line of succession rules, he is the true heir to the Iron Throne—and not his aunt, Daenerys, because the Seven Kingdoms favor male heirs.

Here's how the GoT Wikia describes succession:

Women, even noble-born women, do not have the same legal standing as men. Inheritance only falls on a woman if there are no males in her family ahead of her in line of succession. However, women can rule in their own right if they have no surviving brothers (and their brothers left no surviving heirs). An exception is Dorne, which allows equal inheritance. If the noble-born heir to a lordship is underaged (or otherwise infirm and unfit to carry out their duties), a regent may be appointed to rule in their name.

If Robert's Rebellion had not happened and Robert hadn't usurped the Iron Throne (with help from the Lannisters), Rhaegar would have been next in line after the Mad King.

But the Mad King, Rhaegar and Rhaegar's baby son Aegon with first wife Elia were all dead by the time the show started. Viserys, Dany's brother, believed he was the rightful king while they lived in exile—but he died in Season 1, leading to Dany believing she is the only living Targaryen and that it is her destiny to rule the Seven Kingdoms.

But now we have Jon, who is already King in the North, a title he took on somewhat reluctantly at the end of Season 6, but seems to have finally become at ease with. Remember, in Sunday's episode, he told Dany, "I am a king," with serious conviction.

Little does he know he is a king, but not just in the North. Yet.

Game of Thrones airs Sundays at 9 p.m. on HBO.

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