Lives of Mildreth, a seventh-century nun and abbess of Minster-in-Thanet, were produced between the late tenth and sixteenth centuries in Latin, Old English, and Middle English. In Latin and Old English, her vitae are extent in Historia Regum, a version found in Oxford, Bodleian Library, Bodley 285, Goscelin of St. Bertin’s Vita Deo delectae virginis Mildrethae, and S. Mildryð. One of the Old English versions (London, British Library, Cotton MS Caligula A. xiv) is considered to have been based on a material written by monastic women for their community in Minster-in-Thanet. From the fourteenth century onward, her vitae are included in John of Tynemouth’s Sanctilogium Angliae, the South English Legendaries, Nova Legenda Anglie, and the Kalendre of the Newe Legende of Englande. Lives of Mildreth are both important historical sources for one of the holy women in the Kentish royal family and provide an interesting hagiographic narrative of a nun and abbess in early medieval England.