Maria was Queen of Sicily and Duchess of Athens and Neopatria from 1377 until her death. Born in Catania, she was the daughter and heir of Frederick the Simple by his first wife Constance of Aragon. As she was thirteen years old at the time of her father's death in 1377, her government was effectively taken over by four baronial families who styled themselves "vicars".
In 1379 she was kidnapped by count William Raymond of Montcada, Sicilian nobleman and member of the Aragonese House of Montcada, to prevent her marriage with Giangaleazzo Visconti, Duke of Milan, and imprisoned for two years at Licata. Montcada's move had been approved by her grandfather King Peter IV of Aragon. In 1382 Maria was rescued by an Aragonese fleet; she was taken first to Sardinia, then, in 1384, to Aragon, where she was married to Martin the Younger, the grandson of Peter IV (1389).
In 1392 Maria and Martin returned with a military force and defeated the opposing barons, ruling jointly until Maria's death in 1401.