[1] The barons of the Latin Empire of Constantinople offered to elect John of Brienne co-ruler of their minor emperor, Baldwin II, in 1229.
[2] John accepted the offer and the terms of his election were included in a treaty in Perugia in April 1229.
[2] The treaty stipulated that John's three sons were entitled to rule Epirus and Macedonia if he could occupy the two regions from the Greek ruler, Theodore Komnenos Doukas.
[2] Louis and his two brothers left Constantinople in the retinue of Baldwin II who went on a tour in Europe to seek military assistance against the enemies of the Latin Empire in 1236.
[1] The chronicler also recorded that King Louis IX of France, who was the three brothers' cousin, received them "honorably and graciously".