Jefimija is the name by which Jelena Mrnjavčević (1349-1405) is known. A Serbian noblewoman, she is considered the first female Serbian poet. Her writings have survived and form part of the canon of medieval Serbian literature, and works she made by hand, including embroidery and engraving, have also been preserved.
She belonged to the Serbian nobility. Her father, Vojihna, was a caesar and a member of a collateral branch of the Nemanjić dynasty. She married Jovan Uglješa Mrnjavčević, of the ruling House of Mrnjavčević, and the couple had at least three children: two sons and a daughter, the only one who reached adulthood. After her husband's death, her mother became a nun under the name Jevpraksija and in 1358 made a substantial donation to the Koutloumousiou monastery.
Her best-known texts are the Lament for a Dead Son and the Encomium of Prince Lazar. The lament for her younger son was engraved on the back of a diptych, a two-panelled icon showing the Virgin and Child, which Teodosije, Bishop of Serres, had given to the infant Uglješa at his baptism. Uglješa died at about four years old and was buried at the Hilandar monastery, beside his maternal grandfather Vojihna.
Beyond writing, Jefimija was also a skilled embroiderer and engraver, and some of her pieces have survived to the present day. She is included among The 100 most prominent Serbs, a sign of her lasting place in her country's cultural memory.