For anyone who watched Game of Thrones, the Targaryens are a legendary family line. By the time the series started, their house was seemingly all but gone after being ousted from the Iron Throne. One of the major plots in the series was Daenerys Targaryen's journey to returning her family to the seat of power in Westeros. That included the eventual revelation that Jon Snow was both a secret Stark and a secret Targaryen.

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As the Game of Thrones prequel series House of the Dragon gets closer to launching, fans have a lot of questions about the Targaryens that need to be answered. Additionally, there are some odd facts that not everyone knows about them viewers should keep in mind before the next story begins.

10 There Used To Be Other Dragonlords

Drogon melts the Iron Throne

During the course of the series, fans knew the Targaryens best as dragonlords. Even though their family line as well as almost the entire species of dragons were all but broken, they were still perceived that way.

But before the Doom of Valryia, there were several other families who identified as dragonlords as well. The Targaryens were the only family to survive the cataclysm, or that's at least what fans have been led to believe so far.

9 Robert Baratheon Had Targaryen Blood

Robert Baratheon enjoys a drink at a tourney in Game of Thrones

The Targaryens ruled over Westeros from the Iron Throne in the Red Keep for a long time. Well, that was until one of them went crazy— and Robert Baratheon led a rebellion against the Targaryen's to bring them down.

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What never got talked about enough was the fact that Robert had Targaryen blood coursing through his veins. He was actually the cousin of King Aerys II Targaryen, the ruler Robert sought to overthrow in the first place.

8 They Know The Secrets Of The Red Keep

Varys and Tyrion talk near the Red Keep

As important as different families are to the story, so are specific castles. Each major kingdom and family is associated with particular castles, many of which are the seats of power in different regions around Westeros and beyond.

The Targaryens established the Red Keep in King's Landing as the literal seat of power for the Seven Kingdoms. But there are, or were, a lot of secrets hidden within its walls. Only the Targaryens knew all of the secrets hidden throughout the Red Keep, many of which were lost with its destruction.

7 A Targaryen Civil War Killed Their Dragons

Daenerys and Tyrion walk near Rhaegal and Viserion in Game of Thrones

Even a family as powerful and dominant as the Targaryens had its own internal problems. Many years before the events of Game of Thrones, a civil war broke out between Aegon II and Rhaenyra over who would succeed their father, Viserys I.

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Both children died in the war which ended with Aegon III ascending to the Iron Throne. But the other result of this civil war was the virtual extinction of all of the Targaryen's dragons, something that left them vulnerable to attacks from other houses. Their power was directly associated with their dragons.

6 Other Targaryens Failed To Hatch Dragon Eggs

Daenerys stands with her greatest supporters

As Daenerys Targaryen began her long journey back to the Iron Throne and the redemption of her family name, she was gifted three dragon eggs. She would eventually walk through fire, successfully birthing them and changing her into the Mother of Dragons.

But she was not the first Targaryen to try to hatch dragon eggs after the civil war. Everyone else who did so failed miserably and often died in the attempt. Daenerys hatching those eggs was a massive deal for a multitude of reasons.

5 The Importance Of The Blackfyre Bloodline

Daenerys surveys her army

House Blackfyre is an extinct offshoot of the main Targaryen house and bloodline. It was founded by Daemon Blackfyre, the bastard son of King Aegon IV. On his deathbed, Aegon IV legitimized all of his bastards and ignited another battle for control of Westeros.

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After attempting to overthrow the Targaryens on at least five occasions, House Blackfyre was finally defeated and is presumably extinct. That being said, there members of the line still rumored to be lurking around Westeros.

4 This Family Founded The Kingsguard

Jaime Lannister of the Kingsguard

For anyone who sits on the Iron Throne, they can be guaranteed to have the protection of the Kingsguard. Or in the case of the different women who have led Westeros over the years, the Queensguard. In either case, this royal guard is made up of the greatest knights and warriors from around the kingdom.

It was the Targaryens who first founded the Kingsguard in the first place. This was one of their better ideas as this group is the final line of protection for the ruler of Westeros, and are usually pretty trustworthy. Well, except for a couple of very notable situations.

3 Why They Selected King's Landing For Their Throne

The Iron Throne From HBO's Game of Thrones

King Aegon I Targaryen, King of the Andals and the First Men, established King's Landing as the main seat of power in Westeros. It started as a small wooden fort on a hill called Aegonfort, and grew over the centuries into a massive city of approximately half a million people.

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While it would be easy to say that Aegon I set up shop there for some weird mystical reason, it was far more practical. When he left Dragonstone behind, he built his throne there as it was sparsely populated and offered easy access to the sea as well as other resources.

2 Escaping The Doom Of Valyria

Daenerys surveys her armies after taking King's Landing

Spanning much of Essos, the Valyrian Freehold was incredibly dominant. It was home to advanced magic and technology as well as dragons. All of this combined made the region incredibly dominant throughout the known world.

But the Doom of Valyria utterly annihilated the region, leaving only Dragonstone relatively unharmed. It was from Dragonstone that Aegon I launched his plot to conquer Westeros. What happened to Valyria and why has largely been lost to history, and the supposed end of the Targaryens hasn't helped that.

1 Secret Targaryens Are Everywhere

Jon Snow in Game of Thrones.

When Game of Thrones started, Targaryens were believed to be all but extinct. As the series went on, an increasing number of people who were high ranking members of other houses were revealed to have Targaryen blood coursing through their veins.

At this point, the tendrils of the Targaryen family line have weaved their way into virtually every other major and minor house in Westeros. It's gotten to a point that no one knows for sure who is or isn't a Targaryen. Adding to the intrigue of the situation, who could be a secret Blackfyre is also suspect.

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