Overview
Agnes of Poland (, ; b. c. 1137 - d. aft. 1182) was a member of the House of Piast and by marriage princess of Pereyaslavl and Volynia and grand princess of Kiev since 1168.
Early years
Agnes was the penultimate child and youngest daughter of Duke Bolesław Wrymouth of Poland and his second wife, Salomea of Berg. The date of birth is known thanks to Ortlieb, benedictine monk of Zwiefalten who visited the court of Dowager Duchess Salomea in Łęczyca between 1140 and early 1141; in his reports, he mentioned that Agnes was three years old. As in 1138 Salomea gave birth the future Casimir II the Just, Agnes was born a year earlier.
She was probably named after the wife of his half-brother Władysław II, Agnes of Babenberg. It is also possible that she was named after his father's half-sister, the abbess of Gandersheim and Quedlinburg.
In 1141 Salomea of Berg organized a meeting in Łęczyca, where his eldest sons (Bolesław IV and Mieszko III), and the lords had to decide, among other things, the future of Agnes. They had two options: sent her to the Benedictine monastery in Zwiefalten (where her older sister Gertruda was already a nun) or married her with one of the ruling princes of that time. Eventually it was decided the alliance with Kievan Rus', and thus gain an ally against Władysław II. According to the majority of historians, the chosen groom was Prince Mstislav Iziaslavich. This hypothesis is supported by the fact that ten years later he married Agnes. The second view as a candidate for the hand of Agnes was one of the sons of the Grand Prince of Kiev, Vsevolod II Olgovich. Soon after, he reject the proposal of the Junior Dukes and their mother and choose the alliance with Władysław II, reinforced in 1142 when his eldest son Bolesław married with Vsevolod II's daughter Zvenislava.
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