St Dewi is the saint's name of which David is the English approximation. He was an abbot-bishop of Wales in the sixth century. According to legend he was the son of a chieftain of Cardiganshire, who founded monasteries, attended councils and relocated the chief diocese of Wales from Caerleon to what is now St David's. The source for this information is a life of around 1090, which is not usually considered very trustworthy.

His traditional emblem is the dove, and he appears here between figures representing the bardic tradition (harp, mistletoe and oak) and that of learning (book and lamp of learning).
The work of Sir Edward Poynter, this mosaic was installed in 1869.

Additional Information on
St David for Wales

Unfortunate experiences with frescoes at the Palace of Westminster led the Fine Arts Commissioners to change their original plan, and commission mosaics for the four patron saints in the Central Lobby. Interest in mosaics in the 19th Century had been growing, fuelled by the enthusiasm of Dr Salviati, the man responsible for restoring the mosaics at St Mark's in Venice.

Dr Salviati's firm was then commissioned by the Fine Arts Commission to undertake the implementation of mosaics in Central Lobby - from the designs of Sir Edward Poynter (1836-1919). Saint George and Saint David were installed in 1869.