Some sources give his mother as Maria Marzani,[4] while others suggest he was the result of one of his father's extramarital affairs.

[5] The name Carlo was given to the child at the baptismal font to please Queen Giovanna II of Naples, in memory of her father Charles III of Anjou-Durres.

He spent the early part of his life serving in the military, but soon grew tired of the profession of arms.

At the monastery he dedicated himself to his studies and wrote various religious epistles, orations, moral treatises, essays on the gospels and four books on Scholastic Theology.

In order to respond to the needs of his people, he urged his brother Francesco to build the Ospedale Maggiore, one of the first community hospitals in Europe.