Marriages of the Mazovian Piasts with Princesses of Ruthenian Lineage in the Thirteenth and Fourteenth Centuries

The Mazovian dukes married Ruthenian princesses four times: these were the marriages of Conrad I with Agaphia, daughter of Sviatoslav Igorevich; Boleslaus I with Anastasia, the daughter of the former Prince of Belsk, Alexander Vsevolodovich; Siemovit I and Pereyaslava; and the one between Troyden and Mary, daughter of George I, Prince of Halych. Each of these marriages was arranged in particular circumstances and was aimed to achieve certain political goals. The article discusses the political situation that lead to and resulted from these matrimonies. The marriage of Conrad I and Agaphia was arranged to strengthen the alliance between the sons of Casimir the Just and Sviatoslav Igorevich, father of Agaphia. This alliance did not last long, but despite its dissolution and the death of Sviatoslav, Conrad I did not decide to break his marriage with Agaphia and send her away. The marriages of Boleslaus I with Anastasia and Siemovit I with Pereyaslava, contracted almost simultaneously, secured the eastern borders of the Duchy of Mazovia and provided Daniel of Halych with a strong Polish ally who could be engaged in the military coalition against Yotvingian tribes. In the following years Siemovit and Daniel cooperated in achieving their political and military objectives many times over, and Siemovit even participated in the coronation ceremony of his Ruthenian ally. The matrimony of Troyden and Mary was arranged to renew and strengthen good relations between the Piasts of Mazovia and Rurikids. The momentous political implications of this marriage were revealed many years later, when Boleslaus, son of Troyden and Mary, became the ruler of Galicia and Volhynia. The article is based on medieval written sources – mainly chronicles and annals – of Polish and Ruthenian origins that were confronted with relevant historical studies.