Sack of King's Landing

After the Battle of the Trident, Tywin Lannister marched on King's Landing at the head of twelve thousand men. He had stayed out of the war until then, and now stood before the capital's gates swearing loyalty to King Aerys II.

Inside the city, Grand Maester Pycelle talked the king into letting him in, over Varys's objections. Pycelle believed the realm needed a new king now that Rhaegar was dead, and he was betting on Tywin.

The gates opened. Lannister soldiers marched in and, acting in Robert Baratheon's name, began tearing apart the city they claimed to be defending.

With the city falling around him, Aerys ordered his newest Hand, Wisdom Rossart, to light the wildfire hidden beneath King's Landing for years. If Robert wanted the throne, he said, let him inherit bones and ashes.

He gave the task of killing Tywin Lannister to his own son Jaime, who wore the white of the Kingsguard. Jaime never touched his father: he killed Rossart before the order could be carried out, then killed Aerys himself on the Iron Throne.

Two of Tywin's knights, Ser Gregor Clegane and Ser Amory Lorch, were sent up into Maegor's Holdfast. No one of royal blood would be left alive there to challenge Robert for the throne.

Gregor killed Rhaegar's young son, Prince Aegon, in front of his mother, Princess Elia Martell, then raped and killed Elia too. Amory found Princess Rhaenys hidden beneath what had been her father's bed and did not stop until she was dead.

With those deaths, House Lannister made it plain which side it had really been on, whatever its banners said.

Eddard Stark reached the city with the bulk of the rebel army once it was already over, and found Jaime Lannister occupying the Iron Throne, Aerys's lifeless body lying nearby.

Tywin came before Robert carrying more than words: the body of Rhaegar's wife and the bodies of their two children, wrapped in his house's red cloaks, proof that House Lannister had broken with the Targaryens for good.

Eddard argued with Robert over what those bodies meant. Nothing was settled that night, and Eddard left King's Landing to finish the war on his own terms, in the south.

Eddard rode south and lifted the siege of Storm's End. From there he pushed on to the Tower of Joy, where he found Lyanna, his sister, with her life nearly spent.

Only once Lyanna was dead, sharing the same grief, did Eddard and Robert make peace.

Back in King's Landing, survivors of the sack who had served the Targaryens, men like Ser Jaremy Rykker and Ser Alliser Thorne, were given a choice: take the black at the Wall, or die.

Years later, during his own exile, Tyrion Lannister learned that Prince Aegon had not died that day. Varys had smuggled him out of the city before the sack, putting a peasant family's son in his place, and kept him hidden until he could get him to the Free Cities.

The news undid a story everyone thought was closed. If Aegon lived, the sack had not ended Rhaegar's line — only the version of it Tywin chose to tell that night before the Iron Throne.