[1] Marie served as regent for her younger brother, Baldwin II, Latin Emperor, in 1228, and styled herself "Empress of Constantinople."
Her father Peter was chosen as emperor in 1216, but in 1217, while attempting to reach Constantinople by land, he was captured by Theodore Komnenos Doukas, the ruler of Epirus, and spent the remainder of his life imprisoned.
One of her stepdaughters, Maria Laskarina, became the wife of King Béla IV of Hungary, and the other, Irene Lascarina, was married to John III Doukas Vatatzes who took over the throne of the Nicaean Empire.
In late January 1228, Robert died and was succeeded by his younger brother, Baldwin II of Courtenay.
The barons of Constantinople elected Marie regent, and she styled herself "Empress", but her regency lasted only until her own death eight months later.