Vratislaus II of Bohemia
Church attitudes toward written translations and the use of the vernacular in Mass varied by the translation, the date and location. For example, whereas the acts of Saint-Gall contain a reference to the use of a vernacular interpreter in Mass as early as the seventh century, and the 813 Council of Tours acknowledge the need for translation and encouraged such, in 1079, Duke Vratislaus II of Bohemia asked Pope Gregory VII for permission to use Old Church Slavonic translations of the liturgy, to which Gregory did not consent.