What is Aegon’s Dream and the Prince That Was Promised in House of the Dragon?

As the King strives for a male heir, he must also contend with his roguish brother Prince Daemon Targaryen (Matt Smith) vying for the crown himself, along with the other schemers at court.

However, could Viserys's ideal heir actually be in his only legitimate child, Princess Rhaenyra Targaryen (Milly Alcock, Emma D'Arcy)?

In the first episode, titled The Heirs of the Dragon, Viserys shares some secrets of ruling with Rhaenyra.

So, just what was Aegon's Dream, the Song of Ice and Fire, and the Prince That Was Promised in House of the Dragon?

What is Aegon’s Dream and the Song of Ice and Fire?

Towards the end of the first episode of House of the Dragon, King Viserys tells Princess Rhaenyra how it was a dream that stirred King Aegon I Targaryen to cross over Blackwater Bay from the island of Dragonstone to conquer the Seven Kingdoms of Westeros.

It was in this dream that Aegon saw a future where an endless winter will come down from the North with a terrible darkness riding within it to destroy the world of men, ending all life in this world.

Viserys notes, however, that a Targaryen must be leading Westeros – either a man or woman – to be the Prince Who Was Promised to defend the land of the living against this evil.

The dream was called The Song of Ice and Fire, and Viserys notes that Targaryen monarchs since Aegon have passed on the knowledge of this prophecy to their successors – and now, Viserys is telling Rhaenyra as he plans to make her his heir.

Of course, this prophecy actually fortells the events of Game of Thrones and the Army of the Dead that comes commanded by the White Walkers and the Night King.

In Game of Thrones season 8 episode 3 (The Long Night), it is a union of the realms of men, led by the Targaryen descendants Queen Daenerys Targaryen and King Jon Snow (Aegon Targaryen), who are able to defeat the army and save Westeros, albeit with Arya Stark delivering the killer blow to the Night King.

In the novels, no such dream of Aegon's is mentioned nor are its ideas passed down to Targaryen monarchs as shown in the series.

In the book A Dance with Dragons, Ser Barristan Selmy tells Daenerys that it was said King Jaehaerys II Targaryen was warned by a witch that one of his line would be the Prince That Was Promised, prompting the King to have his children incestuously marry each other thereafter.

However, in A Clash of Kings, Daenerys experiences visions in the House of the Undying in the city of Qarth and has a vision of her older brother Crown Prince Rhaegar Targaryen holding his baby son - apparently by wife Princess Elia Martell - and naming him Aegon.

Rhaegar looks at Elia (and at Daenerys) and says: "Aegon. What better name for a king... He is the prince that was promised, and his is the song of ice and fire."

He then adds: "There must be one more. The dragon has three heads."

Who is the Prince That Was Promised?

Game of Thrones never truly answered this question firmly.

The gender-neutral nature of the High Valyrian language means the prophecy is really 'the Prince or Princess That Was Promised'.

The series offered some possible candidates, with the most notable being Jon Snow (Kit Harington) - born Prince Aegon Targaryen - and Queen Daenerys Targaryen (Emilia Clarke), as both were paramount in leading the alliance of men against the Army of the Dead.

However, it should be noted that in the series, it is Arya Stark (Maisie Williams) – who is not a Targaryen – who is the one to deliver the fatal blow to the Night King which in turn destroys his army of the undead.

Ultimately, the television series never truly answered this properly.

In the A Song of Ice and Fire novels, the prophecy remains unanswered, too. However, further criteria was given as this individual would be considered a reincarnation of the ancient warrior Azor Ahai, who used the fiery sword Lightbringer to defeat a similar evil centuries prior in a time called the Long Night.

The recurring phrase "the dragon has three heads," which was connected to Daenerys's visions surrounding the prophecy, suggested it could have been multiple people working together.

Either way, this has not been answered entirely in the television franchise or the novels themselves.

Read More

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House of the Dragon airs on Sky Atlantic and is available on NOW. Check out more of our Fantasy coverage or visit our TV Guide to see what's on tonight.

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