The maesters of the Citadel who keep the histories of Westeros have used Aegon’s Conquest as their touchstone for the past three hundred years. Birth, deaths, battles, and other events are dated either AC (After the Conquest) or BC (Before the Conquest).
True scholars know that such dating is far from precise. Aegon Targaryen’s conquest of the Seven Kingdoms did not take place in a single day. More than two years passed between Aegon’s landing and his Oldtown coronation . . . and even then the Conquest remained incomplete since Dorne remained unsubdued. Sporadic attempts to bring the Dornishmen into the realm continued all through King Aegon’s reign and well into the reigns of his sons, making it impossible to fix a precise end date for the Wars of Conquest.
Even the start date is a matter of some misconception. Many assume, wrongly, that the reign of King Aegon I Targaryen began on the day he landed at the mouth of the Blackwater Rush, beneath the three hills where the city of King’s Landing eventually stood. Not so. The day of Aegon’s Landing was celebrated by the king and his descendants, but the Conqueror actually dated the start of his reign from the day he was crowned and anointed in the Starry Sept of Oldtown by the High Septon of the Faith. This coronation took place two years after Aegon’s Landing, well after all three of the major battles of the Wars of Conquest had been fought and won. Thus it can be seen that most of Aegon’s actual conquering took place from 2-1 BC, Before the Conquest.
The Targaryens were of pure Valyrian blood, dragonlords of ancient lineage. Twelve years before the Doom of Valyria (114 BC), Aenar Targaryen sold his holdings in the Freehold and the Lands of the Long Summer and moved with all his wives, wealth, slaves, dragons, siblings, kin, and children to Dragonstone, a bleak island citadel beneath a smoking mountain in the narrow sea.
At its apex Valyria was the greatest city in the known world, the center of civilization. Within its shining walls, twoscore rival houses vied for power and glory in court and council, rising and falling in an endless, subtle, oft-savage struggle for dominance. The Targaryens were far from the most powerful of the dragonlords, and their rivals saw their flight to Dragonstone as an act of surrender, as cowardice. But Lord Aenar’s maiden daughter Daenys, known forever afterward as Daenys the Dreamer, had foreseen the destruction of Valyria by fire. And when the Doom came twelve years later, the Targaryens were the only dragonlords to survive.
Dragonstone had been the westernmost outpost of Valyrian power for two centuries. Its location athwart the Gullet gave its lords a stranglehold on Blackwater Bay, and enabled both the Targaryens and their close allies, the Velaryons of Driftmark (a lesser house of Valyrian descent) to fill their coffers off the passing trade. Velaryon ships, along with those of another allied Valyrian house, the Celtigars of Claw Isle, dominated the middle reaches of the narrow sea, whilst the Targaryens ruled the skies with their dragons.
Yet even so, for the best part of a hundred years after the Doom of Valyria (the rightly named Century of Blood), House Targaryen looked east, not west, and took little interest in the affairs of Westeros. Gaemon Targaryen, brother and husband to Daenys the Dreamer, followed Aenar the Exile as Lord of Dragonstone, and became known as Gaemon the Glorious. Gaemon’s son Aegon and his daughter Elaena ruled together after his death. After them the lordship passed to their son Maegon, his brother Aerys, and Aerys’s sons, Aelyx, Baelon, and Daemion. The last of the three brothers was Daemion, whose son Aerion then succeeded to Dragonstone.
The Aegon who is known to history as Aegon the Conqueror and Aegon the Dragon was born on Dragonstone in 27 BC. He was the only son, and second child, of Aerion, Lord of Dragonstone, and Lady Valaena of House Velaryon, herself half-Targaryen on her mother’s side.
Aegon had two trueborn siblings; an elder sister, Visenya, and a younger sister, Rhaenys. It had long been the custom amongst the dragonlords of Valyria to wed brother to sister, to keep the bloodlines pure, but Aegon took both his sisters to bride. By tradition, he was expected to wed only his older sister, Visenya; the inclusion of Rhaenys as a second wife was unusual though not without precedent. It was said by some that Aegon wed Visenya out of duty and Rhaenys out of desire.
All three siblings had shown themselves to be dragonlords before they wed. Of the five dragons who had flown with Aenar the Exile from Valyria, only one survived to Aegon’s day: the great beast called Balerion, the Black Dread. The remaining two dragons — Vhagar and Meraxes — were younger, hatched on Dragonstone itself.
A common myth, oft heard amongst the ignorant, claims that Aegon Targaryen had never set foot upon the soil of Westeros until the day he set sail to conquer it, but this cannot be true. Years before that voyage, the Painted Table had been carved and decorated at Lord Aegon’s command: a massive slab of wood, some fifty feet long, carved in the shape of Westeros and painted to show all the woods and rivers and towns and castles of the Seven Kingdoms. Plainly, Aegon’s interest in Westeros long predated the events that drove him to war. As well, there are reliable reports of Aegon and his sister Visenya visiting the Citadel of Oldtown in their youth, and hawking on the Arbor as guests of Lord Redwyne. He may have visited Lannisport as well; accounts differ.