Aegon Targaryen is a name used for several different Targaryens, so “what happened to Aegon Targaryen” depends on which one you mean.

Below is a quick, spoiler-heavy scoop for the most–asked versions from the books/series.

Aegon II Targaryen (Dance of the Dragons era)

  • Aegon II is the king who fights his half‑sister Rhaenyra in the Targaryen civil war known as the Dance of the Dragons.
  • He’s badly burned and crippled in battle at Rook’s Rest when his dragon Sunfyre clashes with Princess Rhaenys and Meleys.
  • After Rhaenyra takes King’s Landing, Aegon is smuggled out, then later returns, has Rhaenyra killed by Sunfyre, and briefly “wins” the war.
  • His reign ends when he is poisoned in King’s Landing; several of his own political allies are later executed or punished for their roles.

Aegon I Targaryen (Aegon the Conqueror)

  • This is the original Aegon who unites almost all of Westeros with his sisters and their dragons, founding the Targaryen dynasty.
  • What “happens” to him is relatively simple: he conquers, rules, and dies peacefully compared to later Targaryens, passing the throne to his son Aenys.

Aegon V Targaryen (“Egg”)

  • This is the “Egg” from the Dunk & Egg stories, later crowned Aegon V (“Aegon the Unlikely”).
  • He tries to bring back dragons by hatching eggs at Summerhall, but something goes catastrophically wrong.
  • Aegon V, his son Prince Duncan the Small, Ser Duncan the Tall, and others die in the resulting fire at Summerhall.

Aegon Targaryen, son of Rhaegar (book canon)

  • In the books, Aegon is the baby son of Rhaegar Targaryen and Elia Martell in King’s Landing during Robert’s Rebellion.
  • Officially, he is killed when Lannister forces sack the city: Gregor Clegane smashes the infant against a wall.
  • Later, it’s revealed that the spymaster Varys may have secretly swapped the real Aegon with another baby; a young man raised as Aegon appears in the story claiming to be this “saved” prince.
  • In the published books so far, his final fate is still unresolved; he’s alive on page and moving against the Lannisters.

Aegon Targaryen in the TV show (Jon Snow)

  • In the HBO series, Jon Snow learns his real name is Aegon Targaryen, son of Rhaegar and Lyanna Stark.
  • After killing Daenerys in the throne room, he’s exiled back to the Night’s Watch and then heads north of the Wall with the Free Folk in the series finale.
  • The show ends with him alive, living beyond the Wall; there’s no on‑screen death or later canon continuation yet.

Tiny HTML table of key fates

[1] [2] [3] [4]
Which Aegon Targaryen? Era / Context What happened to him?
Aegon II Targaryen Dance of the Dragons Battles Rhaenyra in civil war, badly maimed, later poisoned in King’s Landing.
Aegon I Targaryen Aegon’s Conquest Conquers most of Westeros, rules as first Targaryen king, dies and passes throne to Aenys.
Aegon V (“Egg”) Pre–Game of Thrones Becomes king, dies in the mysterious Summerhall tragedy while trying to hatch dragon eggs.
Aegon, son of Rhaegar (books) Robert’s Rebellion & after Officially killed as a baby; later a young man appears who may be the real Aegon, fate unresolved so far.
Aegon Targaryen (Jon Snow – TV) Game of Thrones show Exiled after killing Daenerys, joins the Free Folk beyond the Wall; alive when the show ends.
If you tell me which version you meant (Aegon II, Aegon V/Egg, book‑Aegon, or Jon Snow‑Aegon), I can zoom in on just that storyline with more detail and theories.