Jon Snow is a Targaryen on 'Game of Thrones,' here's the definitive proof

It's becoming more obvious that Jon Snow is a member of the royal Targaryen family, with a strong claim to the Iron Throne.

The Aug. 13 episode made the strongest allusion yet to the identity of his parents in an unexpected scene. And if we had any doubts, John Bradley, who plays Samwell Tarly, put them (almost) entirely to rest in a recent interview about Episode 5. 

"That scene is probably the most important scene in the show so far, because it's all about Jon Snow's parentage and lineage and what he's entitled to and what he's the rightful successor to," Bradley tells USA TODAY.

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As the hit series heads for its season finale Sunday, how did we get here?

Evidence has been mounting at an increasingly rapid pace since last season's Game of Thrones' finale. Readers of George R.R. Martin's unfinished book series have long suspected Jon of having a Targaryen bloodline.

Presuming Westeros has no DNA tests or its own version of ancestry.com (tracking the Children of the Forest would be especially tricky), we've put together our own case for the the Stark bastard's true Targaryen heritage.

In the Season 6 finale, Bran Stark, now the Three-Eyed Raven, had a vision in which Ned Stark, Jon's purported father, came upon his sister, Lyanna Stark, just after she had given birth. After showing the baby's face, the scene cut to Jon (Kit Harington), visually cementing the connection. 

After that scene, fans assumed Jon's father must have been Iron Throne heir Rhaegar Targaryen, who is said to have abducted and raped Lyanna in Martin's books, but that was never made explicit. Rhaegar was the son of a Targaryen king, putting him next in line of succession.

Thrones delivered another clue in Season 7's second episode, when Red Woman Melisandre met Daenerys Targaryen (Emilia Clarke), Rhaegar's sister and the mother of dragons. When Melisandre brought up a prophesy that only a prince or princess could "bring the dawn," she said Daenerys had a role to play, "as does another, the King in the North, Jon Snow."

Jon's Targaryen ties became even clearer in Sunday's episode, "Eastwatch." First, Jon had a very sweet encounter with Drogon, one of three notoriously ill-tempered dragons that seem to respond well only to Dany, who carries the Targaryen fire gene. Removing his glove and petting the fire-breathing giant's snout, Jon elicited a purr from Drogon, who likely sensed a familial bond.

Documentary proof underlined the connection later in the episode, when budding reader Gilly (Hannah Murray) discovered a Septon had presided over a secret wedding ceremony involving Prince "Ragger" (her pronunciation of Rhaegar) after he had gained an annulment of his marriage. 

Unless Thrones writers are planning to pull the rug out from viewers, that secret marriage would have been to Lyanna — perhaps putting it into conflict with the kidnap/rape story — and the baby, Jon, would be their legitimate son, making him Dany's nephew and heir to the Iron Throne. 

Hence why Bradley calls it a blockbuster revelation.

Of course, it all depends whether anyone in Westeros connects the dots, and hot-headed Sam isn't helping. With no knowledge of Bran's vision, he might not have made the connection between Rhaegar's wedding and Jon's parentage, but he doesn't even hear Gilly because he's furious at The Citadel's complacent maesters.

Letting rage overcome his ability to listen "is a huge flaw," Bradley says.  

As Sam hustles Gilly and baby Sam out of The Citadel in an attempt to rejoin Jon, he leaves behind the Septon's diary with the marriage reference, Bradley says.

"That piece of information could be completely lost, (that Jon) is legitimately a Stark and a Targaryen. He is technically the rightful heir to the throne," he says. "It's a very tantalizing and ultimately frustrating moment for the audience. The dramatic irony is that the audience has a piece of information that potentially nobody in the show does."

If only viewers could send a message via raven to Westeros.