The ancient church of St. Tydecho, Mallwyd. One of the most prominent rectors of the church was Dr John Davies (c.1567-1644), the scholar and lexicographer. He was appointed vicar of Mallwyd in 1604 and in 1614 he also became responsible for the neighbouring parish of Llanymawddwy. Davies is regarded as one of the foremost Welsh grammarians: his Welsh grammar, 'Antiquae Linguae Britanicae ... Rudimenta', was published in Latin in 1621, followed by his Welsh-Latin dictionary of 1632, 'Antiquae Linguae Britannicae ... Dictionarium Duplex'. In addition, Davies played a vital role in the work of translating Biblical texts into Welsh. He assisted Bishop William Morgan with the translation of the Book of Common Prayer of 1599 and was later chiefly responsible for preparing the edited and highly-popular versions of the Welsh Bible (1620) and the Book of Common Prayer (1621).