Radiocarbon-dating carried out on the skeletons, found at a monastic cemetery at the site of a medieval chapel, has revealed the remains are the oldest monks ever to be discovered in Britain.
An artists impression of the site of the medieval chapel
At least 50 skeletons have been excavated at the site since 1960; almost all of them adult males.
Site director Richard Brunning from the South West Heritage Trust said: "It is great to show that a community excavation can produce results that revolutionise our view of the origins of monasticism in Britain and Ireland.
"Archaeology is providing evidence that can get us beyond the uncertainty of the historical sources."
Nerys Watts, Head of HLF South West, said: "This discovery just goes to show the incredible hidden heritage and untold stories still to be discovered within our landscapes."