Euphrosyne of Polotsk was a twelfth-century princess of the Rurik line who became a nun, a copyist of books, and the founder of monastic communities in the lands of Rus' that today lie in Belarus. Born Predslava, by tradition a granddaughter of Vseslav of Polotsk and daughter of Prince George (Georgy) Vseslavich, she was noted from childhood for her love of prayer and book learning. Declining a proposal of marriage, she received monastic tonsure with the name Euphrosyne under the blessing of Bishop Elias of Polotsk. She is commemorated on May 23.
Having taken the veil, Euphrosyne first settled near the cathedral of Holy Sophia in Polotsk, where she occupied herself with the copying of books by her own hand. Around the year 1128 Bishop Elias entrusted her with organizing a women's monastery, and at the Savior-Transfiguration community she taught girls to copy books, to sing, to sew, and to practice other handicrafts. She is also said to have founded a men's monastery dedicated to the Mother of God. Through her efforts a stone cathedral was built in 1161 which, according to the tradition, survives to the present day; at her request the Patriarch of Constantinople sent a copy of the wonderworking Ephesus Icon of the Mother of God.
Shortly before her death Euphrosyne journeyed on pilgrimage to the holy places, accompanied by her nephew David and her sister Eupraxia. After venerating the holy things at Constantinople she came to Jerusalem, where, at the Russian monastery of the Most Holy Theotokos, she reposed in peace; the synaxarion gives the date as May 24, 1173. Her body was afterward transferred to the Kiev Caves monastery, and in 1910 her relics were returned to Polotsk. She is glorified in the Russian Church as a patroness of women's monasticism and is widely venerated as a patron of Belarus.