Aegon V has the nickname "the Unlikely" for his unlikely rise to the throne. He is the fourth son of Maekar I and only ascends to the throne after a Great Council rejects several other heirs and his own brother, Aemon, rejects the throne to remain a maester. After the years of summer during his father's reign, Aegon deals instead with a six-year winter, as well as many uprisings. He also tries to cease the Targaryen practice of incestuous marriages, instead marrying his children off to members of other great Houses.
Aegon, like other Targaryens, spends a great deal of time trying to bring dragons back. This proves to be his downfall, as an attempt to hatch dragon eggs goes tragically wrong and engulfs one of his castles in a brutal fire, killing him and his guests.