[SPOILERS] 'Game of Thrones' may have just confirmed a contentious theory with huge implications for Jon Snow's future

Game of Thrones season seven Jon Snow Helen Sloan HBO (Photo 6)Helen Sloan/HBOJon Snow (Kit Harington) has an important secret bloodline.

Warning: Spoilers ahead for “Game of Thrones” season seven.

Another major piece of the puzzle that is Jon Snow’s parentage was just unveiled on “Game of Thrones.”

While reading old texts with Gilly, Sam Tarly learned that Rhaegar Targaryen — Jon’s father — had his marriage to Elia Martell annulled.

The sixth season finale showed Bran’s flashback to the Tower of Joy, where Lyanna Stark lay dying in a bed of blood after giving birth to Jon. We didn’t see Rhaegar there, nor was there any mention of him, but book readers have long assumed Rhaegar was Jon’s father. HBO even confirmed the theory when they released an infographic in the week after the Tower of Joy scene aired.

And now we know that Jon isn’t just a bastard born from a secret love affair between Lyanna and Rhaegar — he’s likely their legitimate child and could now surpass Daenerys when it comes to the Iron Throne’s Targaryen successor.

Lyanna Stark Ned Jon Snow Tower of Joy Game of Thrones HBOYoung Ned Stark and Lyanna on her death bed with baby Jon.

Rhaegar and Lyanna’s marriage was always hotly contested

“R + L =J” (Rhaegar + Lyanna = Jon) is the oldest fan prediction among fans of George R.R. Martin’s “A Song of Ice and Fire” series. For a full rundown of that theory, read our analysis of all the book and show clues. But even though most people got on board with the assumption that Rhaegar and Lyanna were Jon’s parents, the circumstances around their union was always a fierce topic of debate.

I was a panelist at the Con of Thrones recently, and one of the discussions I moderated was a “R +L =J” panel. The room was packed with around 150 people, and towards the end of our allotted 50 minutes the crowd was literally yelling over each other in debate over Rhaegar and Lyanna’s relationship.

Martin has been deliberately vague in his published books so far about Rhaegar and Lyanna’s relationship, which means fans have had to fill in the blanks with their own assumptions. A search through the “A Song of Ice and Fire” subreddit or Westeros.org forums will show you many discussions among diehard fans about this very topic.

S1E1 Robert Baratheon and Ned Game of ThronesHBORobert and Ned spoke about Lyanna in the crypts on season one.

The story told by most people in Westeros is that Rhaegar kidnapped Lyanna, raped her, and then she died as a result of either the repeated assaults or another mysterious tragedy.

Given how honorable men like Barristan Selmy and Ned Stark think about Rhaegar in their point-of-view chapters or on the show, people doubted that Daenerys’ brother was the horrible kidnapping rapist Robert believed. Instead, it made more narrative sense to think that Lyanna and Rhaegar were actually in love and ran away together in a brash act that led to a horrific war and both of their deaths.

But now we know, at least on the show’s version, that Rhaegar and Lyanna were probably actually married.

The divorce twist no one saw coming

Even after fans became convinced that Rhaegar and Lyanna were in love, the question of Jon’s legitimacy was always the next debate. Rhaegar was already married to Elia Martell and they had two children together — Aegon and Rhaenys.

How Jon Snow and Daenerys Targaryen are related Game of Thrones George R.R. Martin/HBO/INSIDERThe Targaryen and Stark family trees.

Book readers always wondered two things: Did Elia know about Lyanna and approve, making their relationship polygamous? Dorne is certainly more progressive when it comes to the idea of mistresses and lovers outside of marriage and polyamory, and Elia was Dornish. Or was Jon simply a bastard born in secret outside of marriage?

The show just handed readers a third and rarely discussed solution. Rhaegar divorced Elia and then married Lyanna instead under the Faith of the Seven, legitmising Jon and making him the next heir in line after the Mad King Aerys and Rhaegar’s deaths.

Divorce is not a concept mentioned often (if at all) in “A Song of Ice and Fire” or “Game of Thrones.” Tyrion and Sansa’s marriage is referred to as a “sham,” but Tyrion seems to hinge that annulment argument on the fact that it was never consummated.

Interestingly, Oberyn Martell might have been hinting at this divorce back on the fourth season.

S4E1 Oberyn and Tyrion Speak about Elia Game of ThronesHBOOberyn was the brother of Elia and wanted to kill the Mountain to avenge her death.

“The last time I was in the capital was many years ago,” Oberyn told Tyrion. “Another wedding: my sister Elia and Rhaegar Targaryen, the last dragon. My sister loved him. She bore his children […] and beautiful, noble Rhaegar Targaryen left her for another woman.”

Maybe Oberyn wasn’t simply referring to a love affair between Rhaegar and Lyanna, but instead it’s possible he knew about the divorce/remarriage situation.

Funny enough, now Bran Stark and Sam Tarly have more information about Jon’s parents than he does. So far Jon is still operating under the assumption that he is Ned Stark’s bastard. How will he react when he learns the truth? And perhaps more importantly, how will Daenerys respond?

Game of Thrones season seven Daenerys Targaryen Jon Snow Helen Sloan HBO (Photo 5) (1)Helen Sloan/HBOJon and Daenerys are aunt and nephew.

This makes Jon her nephew and it means he’s the next legitimate heir to the Iron Throne — not her. The line of succession from Daenerys’ father, the Mad Kind Aerys, would have gone: Rhaegar, Rhaegar’s trueborn son, Viserys, then Daenerys.

Of course, none of this matters if nobody knows the truth and Jon doesn’t seem to be scheduling any meetings with either Bran or Sam anytime soon. We can only hope that someone has a heart-to-heart with Jon and fills him in on everything we now know.

In the meantime, if you’re looking for even more proof of Jon’s parentage, read our roundup of every hint the show has given since the first season.

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