
Roger Sherman Loomis
Roger Sherman Loomis (1887–1966) was an American scholar and one of the foremost authorities on medieval and Arthurian literature. Loomis is perhaps best known for showing the roots of Arthurian legend, in particular the Holy Grail, in native Celtic mythology.
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Books

Celtic Myth and Arthurian Romance
2005
ISBN 9781613732106
Medieval English Verse and Prose
1948
ISBN 9780390575692