Born in Casale, she was the daughter of William VII, Marquess of Montferrat and his second wife Beatrice of Castile.

In 1284, Andronikos II, a widower by his first marriage with Anna of Hungary, married Yolanda (who was renamed Eirene as Empress).

She set up her own court in the city and controlled her own finances and foreign policy until her death fourteen years later.

According to Nicephorus Gregoras, she died of fever in 1317 in the city of Drama, located in present-day northeastern Greece, where she had a residence.

She was initially buried there, possibly in the surviving Church of the Taxiarches, before her daughter Simonis Palaiologina transported her remains to Constantinople.