This chapter examines the musical practices employed by Catholic missionaries among the Wabanaki peoples during the colonial period in what would become the northeastern United States and the Maritime Provinces of Canada. Liturgy, ritual, and hymnody all contained musical styles and sacred genres that made it possible for priests to convert Native Americans, while at the same time Native Americans found ways to retain many distinguishing characteristics of their own religious experiences. The Thomas Kyrie Manuscript provides the central case study in the chapter. Hymn practices grew up around funeral practices. The chapter contributes substantially to understanding how sacred musical practices provided the basis for new practices of literacy and the transformation of Wabanaki society until the present.