Euphrosyne was the first daughter of Grand Prince Mstislav I of Kiev[2] and his second wife, Liubava Dmitrievna Zavidich.

She persuaded King Vladislaus II of Bohemia to give military assistance to her son against the invasion of the Emperor Manuel I Komnenos.

When King Stephen III died on 4 March 1172, she was planning to ensure his succession against her older son, Béla, who had been living in the court of the Emperor Manuel I Komnenos.

King Béla III ordered the arrest of Euphrosyne and kept her confined in the fortress of Barancs (Serbian: Braničevo).

From Constantinople she moved to Jerusalem where she lived as a nun in the convent of the Hospitallers, and then in the Basilian monastery of Saint Sabbas.