Background
Maria was the daughter of self-proclaimed Emperor Simeon Uroš, the half-brother of Emperor Stephen Uroš IV Dušan of Serbia (Nemanjić dynasty), and Thomais Orsini.
Maria was the daughter of self-proclaimed Emperor Simeon Uroš, the half-brother of Emperor Stephen Uroš IV Dušan of Serbia (Nemanjić dynasty), and Thomais Orsini.
Her maternal grandfather was John Orsini of Epirus. In 1366, Maria married Thomas Preljubović, who was appointed governor of Epirus in Ioannina by her father. The population of Ioannina acclaimed Maria as ruler.
She used the title of basilissa, female form of basileus.
John Uroš suggested that Maria marry Esau de" Buondelmonti, one of the Latin noblemen captured by Thomas in 1379. Maria married Esau in February 1385, and survived for a further decade, dying on December 28, 1394.
The Chronicle of Ioannina, so hostile towards Thomas, describes Maria in very flattering terms. The Byzantine historian Laonikos Chalkokondyles suggests that she was an unfaithful wife of questionable morality.
Both accounts may be biased.
Maria does not appear to have had surviving children from either marriage.