He was discovered by Humfrey at the age of six. He succeeded him as King of Xanth at the age of 22.
Four years after becoming king, he declared any human citizen of Xanth not able to demonstrate his or her magic talent by their 25 birthday was to be exiled to Mundania. In the waning years of his administration, the Storm King was viewed as largely ineffective, magically powerless and perhaps senile.  This set the stage for Bink's exile into Mundania and the "Evil Magician" Trent's return to Xanth.
The centaurs near North Village, where Aeolus reigned from, respected him due to some help he once provided for them. During a firefly infestation of their oatfield, Aeolus generated a five day storm to help drown out the fireflies. 
Aeolus reappears in Humfrey's flashbacks in Question Quest, which reveals how and when he was found by Humfrey, ascended to the throne and made his declaration to banish anyone born without magic.
Later, in Xone of Contention, Grey and the golem Robota travel back in time to the events of A Spell for Chameleon and meet King Aeolus in person. During their meeting with him, they learn he is not actually as foolish as he seems. He keeps his soul in a soular cell, created centuries before by Magician Yin-Yang, which prevents aging and death for the person whose soul is stored inside. However, the cell cannot undo aging suffered before that point. Claiming he does not need his soul with him all the time, Aeolus removes his soul from the cell only when he needs to invoke his talent, since it remains with his soul, and pretends to be senile in order to avoid onerous tasks. Grey later notes that since he has no soul most of the time, he also has no conscience, explaining most of his behavior. Despite Aeolus's efforts to stave off death, he is ultimately unsuccessful, dying not too long after the two time travelers leave the village.
- A Spell for Chameleon
- Centaur Aisle, mention
- Question Quest, mention
- Harpy Thyme, mention
- Geis of the Gargoyle, mention
- Roc and a Hard Place, mention
- Xone of Contention