Asen dynasty
Maria (Kyramaria)
Daughter of tsar Mitso and Maria (daughter of Ivan Asen II) and sister of Ivan Asen III. For the sake of her Asen kinship George Terter I set aside his first wife and married her, gaining imperial legitimacy; she was later sent to Byzantium.
Biography
Maria — called Kyramaria in the Synodikon of Boril — was a daughter of Tsar Mitso and Maria (daughter of Ivan Asen II) and a sister of Tsar Ivan Asen III (John III Asen). Of her life before 1278 the sources are silent.
When her brother Ivan Asen III ascended the Tarnovo throne (1279), among the leading men stood out the ambitious boyar George Terter. To bind him to his son-in-law, Emperor Michael VIII arranged for Terter to repudiate his first wife and his son Theodore Svetoslav (taken to Nicaea) and to marry the royal sister Maria, receiving the dignity of despot. Soon Terter easily seized the throne, abandoned by Ivan Asen III (early 1280).
Maria's marriage, however, did not last. Under the peace treaty between George Terter and Andronikos II (1283/84), Terter's first wife and Theodore Svetoslav were returned to Bulgaria, while Maria Asenina was sent to Byzantium; her later fate is unknown. From her marriage to Terter she had a daughter Anna, who around 1284 married the Serbian king Stefan Uroš II Milutin and was Serbian queen for fifteen years.
Sources
“Мария или Кирамария е дъщеря на Мицо и на Мария [I, № 20], сестра на Йоан III Асен.”
— The Asen Family (1186–1460): Genealogy and Prosopography, p. 257