Warning: Contains SPOILERS for House of the Dragon season 1, episode 8, The "Lord of the Tides."House of the Dragon season 1, episode 8, "The Lord of the Tides," completely flips Aegon the Conqueror's Song of Ice and Fire and notions about the Prince That Was Promised. Aegon's dream of White Walkers - or what he saw as a great Winter and darkness coming from the North - has helped to define House of the Dragon season 1. It's knowledge that has burdened King Viserys and yet driven him to action, both believing in his own dragon dreams and also naming his daughter, Rhaenyra, as his heir.

In House of the Dragon season 1, episode 8, though, things go even further. With Rhaenyra previously speaking to him of the dream earlier in the episode, a confused and ailing Viserys talks of Aegon's dream to Alicent, thinking her his daughter. He confirms his belief the dream is real and, seemingly, that Rhaenyra is the Prince That Was Promised... but Alicent, who knows nothing of this prophecy, takes it to mean that her son Aegon is the Prince of whom Viserys speaks, and that he must unite the realm. Where Aegon's dream was before a 300-year thread that started with his conquest and ended with Jon Snow and Daenerys Targaryen helping to defeat the White Walkers, it now threatens to tear the realm in two.

Related: Rhaenyra's Catspaw Dagger Scene Has A Deep Connection To Aegon's Dream

What Viserys Telling Alicent About Aegon's Song Of Ice & Fire Means

House Of The Dragon Alicent Hightower Olivia Cooke

Alicent, totally misunderstanding Viserys' comments, claims she knows what must be done and, in an instant, all the goodwill worked towards in House of the Dragon season 1, episode 8 is undone. Just a few scenes earlier, Alicent had stood and proclaimed Rhaenyra as her future Queen; now, there's no way she will want to let that happen. The bonds of trust that had only just started to reform will be broken, with Alicent now more desperate than ever to put her son, Aegon, on the Iron Throne. She will feel more justified than before in doing so too, believing it to be the dying wish of King Viserys, thinking it will supersede him previously naming Rhaenyra as heir.

This, of course, had to happen regardless - this is the story of the Dance of the Dragons, and so the rival claims were always going to come to a head. But it's a fascinating decision to make Aegon's dream and the Prince That Was Promised be the catalyst (alongside Viserys' death) for the civil war. It's the exact opposite of what Aegon the Conqueror's prophecy foresaw and what he wished for, but does speak to the nature of prophecies in Game of Thrones. So often, they are warped by history and people's own perceptions, and they're less important for what they actually mean than for how people interpret them and make them self-fulfilling.

With that, it makes far more sense House of the Dragon introduced Aegon's dream when, ultimately, the Winter it tells of won't come for centuries. Despite that fact, just carrying its burden and trying to shape or stay true to it has decided its story all the same, from Viserys through to Rhaenyra, and now Alicent and Aegon (though whether she tells her son is another matter; he will be pushed more to become King, but hardly seems ready for the burden of uniting the entire realm). It turns the Dance of the Dragons into a battle of ill-fated prophecy and destiny but also, sadly, of misunderstanding, which provides a throughline from Alicent first turning against Rhaenyra (listening to the words of Larys Strong and Criston Cole), to what she interprets Viserys' wishes to be here.

Related: Rhaenyra & Daemon's Plan & Shocking Decisions: Full Meaning Breakdown

The Prince That Was Promised Starting The Dance Of The Dragons Mirrors GOT

There's a sense of history repeating itself with Aegon's dream being a key instigator of the Dance of the Dragons, in that it mirrors key events that preceded Game of Thrones - namely, Robert's Rebellion. Although The Mad King, Aerys II Targaryen, clearly needed to be removed anyway and discussions were already happening about how best to do so, it wasn't until Rhaegar Targaryen kidnapped Lyanna Stark that Robert Baratheon was truly forced into action and Robert's Rebellion began. That set about a year of battles, unrest in the realm, and a change in ruler (not to mention the end of the Targaryen dynasty), and it too started with The Prince That Was Promised.

Though it's not clear exactly how he came upon it (since it seemingly dies out for a time, perhaps with the Dance of the Dragons), Rhaegar became obsessed with the Prince That Was Promised prophecy - first believing he might be the realm's savior, then coming to realize it referred instead to his son. Rhaegar, however, also believed the dragon would have three heads, as he tells Daenerys in a vision, suggesting he thought he needed three children. While he and Elia Martell had two, she was unable to have any more children after two difficult births, which ultimately led Rhaegar to Lyanna.

Game of Thrones suggested Rhaegar and Lyanna married for love, and that may be true, but it was almost certainly driven as well (at least at first) by The Prince That Was Promised prophecy, and Rhaegar suspecting a child born of a Targaryen and a Stark could help fulfill the Song of Ice and Fire. Thus, two different generations, interpretation the same prophecy in different ways, have unleashed havoc thanks to twisting Aegon's dream.

House of the Dragon releases new episodes Sundays at 9pm ET on HBO.

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