The Real Reason Behind House Targaryen Incest Tradition
Believe it or not, Targaryens do have a reason, even two of them.
Game of Thrones fans most likely found nothing surprising in multiple incest scenes shown in House of the Dragon. But the new viewers might wonder why Targaryens are so keen to marry their sibling children, or why the hottest love story in the show is actually between uncle and niece. So why is House Targaryen so in love with itself?
There are actually two reasons that make sense.
People with Targaryen DNA have a special connection with dragons and the ability to ride them. So if House Targaryen is not willing to lose their jackpot feature, they need to intermarry. It is worth mentioning that Targaryens can marry into other houses for love or useful alliance, but in this case their child will most likely be encouraged to marry someone with Targaryen blood to get back on track.
The second reason is even more noble. Do you remember Aegon the Conqueror's prophecy passed from a Targaryen king to his rightful heir? The prophecy predicts the rise of death and cold from the North and literally says that for the mankind to survive, a King or Queen of Targaryen blood must seat on the Iron Throne and unite the realm. So marrying inside the family strengthens the Targaryens' hold of the Iron Throne and helps them fulfil their mission to save the realm from the Wight Walkers one day.
You might wonder how is incest not a sin under the extremely conservative religion of Westeros where princess Rhaenyra is frowned upon for even the remote chance she had sex before marriage. George R. R. Martin has an answer for this, too. King Jaehaerys, who was a king right before Viserys, appealed to the Faith leadership and obtained an exception for his family. In other words, there is a rule in Westeros that forbids incest, but it doesn't apply to House Targaryen. Convenient, right?
Rest assured, Targaryens are not totally above the religious law. Back in Valyria, Targaryen kings practiced plural marriage, but this tradition didn't hold in Westeros, as we can see from the attempt of Daemon Targaryen to take the second wife in episode 2.
It is also worth mentioning that George R. R. Martin didn't just come up with this idea of incest out of the blue. Most events and characters of the Song of Ice and Fire books are based on real life European royal families who were not unfamiliar with inbreeding themselves. The difference is they didn't have all the dragons to explain incest.