Insane Beard,

An even earlier statement of the full "Raglan Orthodoxy" came in John Speirs's 1957 book Middle English Poetry: The Non-Chaucerian Tradition, in the chapter on Sir Gawain and the Green Knight. Speirs says that the Green Knight is none other than the "Green Man...the Jack in the Green or the Wild Man of the village festivals of England and Europe," and also "descendant of the vegetation or nature god...whose death and resurrection mythologizes the annual death and rebirth of Nature."