How Rhaenyra's Son Aegon III Became Known as the Dragonbane

The last Targaryen dragon in Westeros may have died because one boy grew tired of them and decided to put an end to what he saw as pure craziness and a bad omen. That boy was Aegon III, also known as Aegon the Younger, the son of Rhaenyra and Daemon Targaryen, and he was the king sitting the Iron Throne when the last dragon in the realm finally died.

Aegon III earned the name Dragonbane because the last living dragon died during his reign

The realm gave him that title, Dragonbane, simply because the last living dragon in Westeros died while he was king.

Watching his mother die shaped a hatred and fear of dragons

Because of how he witnessed his mother die, Aegon III developed a hatred and fear of dragons. It is said that he killed the last dragon, though the details of how are murkier than a simple confession.

A rumor, not a confirmed fact, says Aegon poisoned that last dragon

Ser Arlan is quoted saying, "Some say King Aegon poisoned her." That is the actual weight of the claim, a rumor, not an established fact.

Morning survived because Aegon never touched her, so Rhaena kept her dragon

At the time, a dragon named Morning was still a hatchling and harmless. Aegon could have killed her too, but he did not. Morning lived, and because Aegon never touched her, Rhaena got to keep her dragon.

After the last dragon died, Aegon III tried to bring dragons back with sorcery

Aegon III did try to bring dragons back. He brought nine mages across the Narrow Sea from Essos after the last dragon was already dead and buried, and set them to work kindling a clutch of dragon eggs with sorcery.

That raises an obvious question: why would a man rumored to have poisoned the last dragon then spend a fortune trying to hatch the next one?