Kassia was a Byzantine-Greek composer, hymnographer, and poet who lived in Constantinople during the 9th century. She holds a unique and significant place in Byzantine music as the only known woman whose music appears in the Byzantine liturgy, a distinction that underscores both her musical talent and the rarity of women composers in this tradition. Approximately fifty of Kassia's hymns survive to the present day, with most of them being stichera, a form of liturgical poetry. However, at least 26 of her surviving works have uncertain attribution. The questions surrounding authenticity arise from the common Byzantine practice of composing anonymous hymns, as well as instances where different manuscripts attribute the same work to different authors. Kassia served as an abbess of a convent located in the western part of Constantinople, a position that would have given her both religious authority and access to the musical and literary resources of the Byzantine church.