Born at the very end of the year 153, King Daeron II Targaryen, known as Daeron the Good (the Hypocrite-born or False-Lineage by his enemies), was the eldest legitimate son and heir of Aegon IV Targaryen and his wife (and sister) Queen Naerys Targaryen. He acceded to the throne rather late when he was more than thirty years old.
Thin, with tucked shoulders and a slight paunch, Daeron had never been a fighter, but he exuded a great peaceful strength. His physique and the company of his beloved masters put him at odds with the traditionally fighting culture of the Seven Crowns.
Probably because of the many rumors questioning his legitimacy (rumors provoked by his father's behavior, who thought he was the son of Aemon Dragon Knight, in favor of his bastard half-brother Daemon Feunoyr), he wore his father's elaborate crown.
Despite Daemon Feunoyr's rebellion in 196, which was followed by many other Feunoyr attempts to overthrow the Targaryens, Daeron II is considered a competent and peaceful king.
The balance of his reign seems to be positive, the Feunoyr Rebellions being much more the consequence of his father Aegon the Unworthy's reign than his own. Dorne is finally attached to the kingdom, allowing the effective union of the Seven Crowns, desired by generations of Targaryens.
It is Daeron II who convinces his son Maekar to let his son Aemon become Maester at the Citadel, as the realm has many potential successors to the Iron Throne and "too many dragons is as dangerous as too few".