However, we may not actually see Aegon's Conquest in the series. That conflict is so significant that recorded history in Westeros is divided into BC (Before the Conquest) and AC (After the Conquest). That was the destructive war where Aegon Targaryen (later dubbed 'Aegon the Conquerer') waged war on the Seven Kingdoms and ushered in the reign of House Targaryen. Instead, House of the Dragon is set in the era of another formative event in Westerosi history - Aegon's Conquest. That series was set some 5,000 years in the past and likely would have explored the first war between humanity and the White Walkers. That's a pretty significant jump back in time, though not nearly as huge as what we would have gotten from the now-canceled Age of Heroes prequel.
House of the Dragon is expected to be set roughly 200 years before the events of Game of Thrones. House of the Dragon on HBO: The Time Period
