This dissertation examines the unique musical culture of Vadstena Abbey, the Swedish double monastic house (both brothers and sisters) of the Birgittine Order, and uses traditions associated with this culture to begin filling several holes in medieval musicology, medieval studies, and studies of gender in the Middle Ages. I present new details about the chant traditions of a late-medieval, double monastic order, discussing the relationships among music, saints, symbolism, and gender identities. I answer questions about how the Birgittines took symbolic identities for saints and constructed liturgies to elaborate on this symbolism, and how gender identities were created and sustained by women and men in a cloister. Careful detective work with processionals and choir directories has revealed a rich and vibrant world of Birgittine liturgical practice that resounded in the spaces of Vadstena Abbey church throughout the late fourteenth, fifteenth, and sixteenth centuries. This dissertation is divided into three parts: Chapter 1 presents an overview of the central foci for this dissertation: gendered organization of Vadstena Abbey as a double monastery, the different texts that explain Birgittine liturgical practices (not only Birgitta’s revelations, but also the customaries, ordinals, and a devotional treatise), and the four women central to Birgittine devotional practice (the Virgin Mary, St. Anne (mother of Mary), St. Birgitta, and Katarina (Birgitta’s daughter, venerated locally in Sweden but not officially canonized, also first abbess of Vadstena Abbey). Part 2 comprises Chapters 2 and 3, which deal with specific parts of devotional life, namely the architecture of the abbey church and liturgical manuscript production (studied with paleographic and codicological lenses), and their relationship to the liturgy and social organization at Vadstena. Part 3 comprises Chapters 4 and 5, which feature examinations of specific Birgittine feast day liturgies. Chapter 4 is a case study about the multisensory devotional landscape of Stabat Virgo dolorosa, the Swedish office for the Compassion of Mary. Chapter 5 is a survey of processions; processional chants for the Virgin Mary, St. Anne, St. Birgitta, and Katarina serve as the musical objects of study. Together, Chapters 4 and 5 examine devotional networks created by the Birgittine brothers and sisters at Vadstena Abbey.