How Jon Snow and Daenerys are related - A look back at the Targaryen family tree

Warning: contains spoilers

Game of Thrones took a while to reveal the true identity of Jon Snow's father, but die-hard fans of George RR Martin's books have known - or at least suspected - for years. 

Just in case anyone was still in any doubt about the Stark and Targaryen family tree, in 2016 HBO posted a helpful graphic on their website, confirming the name for all to see. The chart confirmed that Jon’s father is Rhaegar Targaryen, the young prince who eloped with Jon’s mother Lyanna Stark to the Tower of Joy.

While the Game of Thrones season six finale showed us, via Bran-vision, that Eddard Stark's sister Lyanna was Jon's mother, it stopped short of spelling out exactly who Jon's father was (although, frustratingly, we did see Lyanna whisper into Eddard's ear, apparently telling him Jon's real name).

At any rate, the beloved fan theory, referred to for years as "R+L=J", was confirmed beyond all doubt in the season 7 finale - again, via a Bran-vision flashback showing Rhaegar and Rhaegar's courtship.

But how exactly are Jon and Daenerys related, and what does this mean for Westeros? In case you need a quick refresher, here are some essential facts:

1. Rhaegar was Daenerys’s older brother - meaning that Jon is Daenerys's nephew

Rhaegar was the eldest child of the Mad King, Aerys II, and, before the rebellion, first in line to the throne. His younger siblings were Viserys (who received his "golden crown" back in season one) and Daenerys. 

He was married to Elia Martell, and had two children with her: Aegon and Rhaeneys. Both children were murdered by Ser Gregor Clegane after the Mad King fell, on the orders of Tywin Lannister, in order to secure Robert's throne. (This may not be true in the books, but that's a whole other can of confusing, Blackfyre-flavoured worms, and probably not worth going into here.)

Oberyn Martell (the Red Viper), who memorably took on The Mountain in season four in single combat, was Elia's brother.

This means that, while the characters are similar in age, Daenerys is actually Jon's aunt.

2. Despite this, Jon and Dany still got together

Hey, it's Game of Thrones. Thanks to Jaime and Cersei, we've grown accustomed to incestuous trists – and, as previously mentioned, the Targaryen tradition of marrying within the family has already been well-established. 

Furthermore, while brother-sister and parent-child incest would have still been taboo, marriages between cousins, and sometimes between uncles and nieces, were also not uncommon in Medieval times (and the show, of course, is set in a quasi-historical past). 

In other words, while it may seem shocking to us, Jon and Dany becoming a couple - as seen in the season 7 finale - won't appall the characters within the world of the show.

It's also worth noting that, as things stand, neither Jon nor Dany has any idea that they're related. This could all change in season eight, though. 

3. Rhaegar's marriage to Lyanna means Jon, not Daenerys, is the 'rightful' heir to the iron throne

Rhaegar was married to Elia Martell at the time he ran away with Lyanna, but thanks to some accidental detective work by Sam and Gilly, we now know this marriage was annulled,  allowing him to legally wed Lyanna. Therefore Jon is a legitimate son, rather than a bastard – meaning that Jon's claim to the iron throne would be stronger than Daenerys's.

While this might sound frustratingly patriarchal, the succession order here in fact has more to do with the right of the first-born than with men automatically trumping women. Because Rhaegar was the rightful heir and eldest brother, his children, male or female, would naturally come before Daenerys in the order of succession.

4. Jon's parents are both dead

Like poor Lyanna, who died in childbirth, Rhaegar was killed before the events of Game of Thrones began, slain in battle by Robert Baratheon (who later went on to become King of Westeros).

Robert was betrothed to Lyanna and very much in love with her, and genuinely believed that Rheagar had kidnapped his bride-to-be. He also never knew that she had had a baby: aware that revealing Jon's true parentage could be fatal, Lyanna's brother Eddard decided to pretend Jon was his own bastard son, and raise him as such.

5. Rhaegar was, like, really good looking

All descriptions of the character in George RR Martin’s books agree upon one thing: the white-haired, violet-eyed Rhaegar was something of a Westerosi dreamboat. There’s even a chapter in which Cersei Lannister recalls meeting him and feeling strongly attracted to him. (Remember how, when she meets the witch Maggy, she asks if she'll "marry the prince" before getting told she'll marry "the king" instead? The prince she was speaking about was Rhaegar... and the king she eventually ends up marrying is Robert.) 

In the finale flashback, Rhaegar was played by British actor Wilf Scolding:

6.  But Jon doesn't take after him (at least colouring-wise)

While most Targaryens, such as Daenerys, are famed for their pale skin and silver locks (and, in the books, violet eyes),  Jon has dark hair and eyes. This doesn't, however, mean that his heritage is in dispute. The Targaryen habit of wedding brother to sister and keeping everything in the family probably helps account for their distinctive family features. In Jon's case, however, the Stark genes are clearly the dominant ones. (We're pretty sure someone, somewhere, is currently writing a dissertation on the subject of "Genetics and Game of Thrones".)

7. He's been painted as a violent rapist/abductor, but all the clues suggest he was really a bit of a hero

Barristan Selmy (brutally killed off back in season five) described Rhaegar as "the finest man I  ever met", and other characters have echoed his account. But the "official" version of the story, peddled by Robert (who genuinely believed it, but also probably needed to believe that his beloved Lyanna had been faithful to him) claims that Rhaegar abducted and raped her. The show has repeatedly hinted that this wasn't the case.

Catch up on season 1-7 of Game of Thrones now with a 7 day free Entertainment Pass trial. To delve into the books series that started it all, order the collection of all seven books, A Song of Ice and Fire, from The Telegraph Bookshop. Call 0844 871 1514 or visit books.telegraph.co.uk