As a contribution to the fascinating subject of attributed arms for legendary and historical characters the following may be of interest:
St. Petrok has been called the Father of Cornish saints, and moreover was widely revered in what are now Devon and Brittany. He is the subject of many legends, and one of these provides the elements for the device shown. Saving a deer from a noble hunter is an act attributed to several saints. In this case the hunter is said to have been the cruel ruler Cossentin or Constantine, who later was converted and himself revered in the Celtic church. The horn of Constantine, allegedly presented by him to Petrok, was over a long period preserved as a sacred relic.
The device shown appears carved in stone at Rialton, near Newquay, the summer residence built by Thomas Vivian, the sixteenth century Prior of Bodmin, whose priory was dedicated to Petrok. The tinctures for this device are unknown, but the field is now commonly represented as gules, the charges generally argent, with the sword-hilt and pommel and the crown in gold.
St. Perran has been confused with the Irish St. Keiran and many legends of varying credibility were attached indiscriminately to both. Long tradition credits Perran with the invention of tin-smelting and with a certain love of the bottle! This latter idea may be based on the riotous celebration of his feast by tin miners in later days.
The simple device of the white cross on a black ground has been interpreted as representing the triumph of good over evil, or as symbolising refined white tin contrasted with the dark tin ore. The eighteenth century historian C. S. Gilbert noted this tradition and described the device as the banner of the Cornish.
The Cornish are said to have fought at Agincourt under a banner depicting two wrestlers in a hitch, while for centuries the Duchy arms, sable bezantee, were used by many Cornish associations, although the Duchy is of course by no means identifiable with Cornwall itself. In modern times the Cornwall County Council has been granted the arms of the Duchy within a bordure barry wavy argent and azure.
Neither the Duchy nor the County Council arms are appropriate for display by Cornishmen in general, and the banner of St. Perran is widely flown as the emblem of the people of Cornwall.