Locus iste: This place. So begins the well-known sung text, or plainchant, forming part of the religious dedication of a building or altar. It can be found in hundreds of musical sources across Europe, from the earliest complete surviving antiphonary to include neumes (probably copied at the Swiss Benedictine monastery of Einsiedeln by Abbot Gregor the Englishman in the years around 960–70) to the printed liturgical books that circulated in the early sixteenth century, and up to the present day.1 The full gradual, Locus iste a Deo factum est inestimabile sacramentum irreprehensibilis est (‘This place was made inestimably sacred by God; it is beyond reproach’), emphasises the permanence and enduring holiness of ceremonial spaces within the Christian church. Its presence served as a performative connection between widely distributed churches and chapels and Rome, the spiritual centre of the Christian West. Religious buildings were all individually designed and decorated, and the unique liturgical books held within each one bear testament to the diverse services that were held there throughout the church year, from daily Mass to occasional rites such as baptism.2 Textual witnesses – manuscripts throughout the pre-Reformation period