Insane Beard,

On the other question of when the Raglanite idea was emerging into popular consciousness, I'd say the books you cite, Anderson et al, are the first step. It picked up speed in the 1960s, and was firmly entrenched by 1967. In that year, Ronald Johnson, the American poet, was able to write The Book of the Green Man. He described the poem as an English seasonal poem, and gets in everything from Robin Hood to Tolkien. In the notes, he wrote the following passage. Note that, although Raglan might not have been aware of the seventeenth-century figure from processions, Johnson was.

Note also the reference to Grigson. Though he doesn't specify, I suspect this is Grigson's 1948 work An English Farmhouse and its Neighbourhood. If I were you, I'd track that down. If Grigson made direct reference to "The Green Man" in this regard, it's an important and very early link in the chain from Lady Raglan into the popular imagination.

Johnson also mentions Nikolaus Pevsner elsewhere in his notes. This important writer on architecture was an early adopter of the name "Green Man" for the Foliate Head. I'd look at his 1945 book The Leaves of Southwell.

Anyway, here's Johnson, followed by some more notes.

"The Green Man" of the title is not a poetic metaphor, merely, but is still to be seen in England. It is not uncommon for pubs or inns to be called by his name, a hold-over from times when he was a current legend and was deeply associated with Robin Hood, and the Green Knight in Gawain and the Green Knight. But he is most often to be found, today, as the face with sad, heavy-lidded eyes occupying the corbel of an arch in churches. There, he has branches growing out of either side of the mouth, or is bearded in leaves with more foliage springing from the forehead, or is garlanded.

    As King of the May, or Jack-in-the-Green, he has a persistent history that can be traced back to May Day celebrations throughout Northern and Central Europe. Geoffrey Grigson writes that traditionally "on May Day in the village plays and ceremonies he was sacrificed dying for all the death of the plants in winter." In former times he was also marched in the London Lord Mayor's Day Parade enclosed in a wooden framework on which leaves were clustered and from which came explosions of fireworks. Chimney sweeps paraded beneath the same pyramidal frameworks on May Day until the nineteenth century. One imagines them coming like small boxwood topiary, crackling and sparkling through the streets.

    Lewis Spence adds a less typical, later variant: "I have seen him at South Queensferry, on the southern shores of the Firth of Forth, where he is know as the 'Burry Man', a boy on whose clothes large numbers of burrs or seed-cases have been so closely sewn that he presents the appearance of a moving mass of vegetation."

    He is also seen, of course, in the guise of Arcimboldo's "portraits" of the seasons or as the fanciful Seventeenth Century Gardener pictured in herbals and gardening books in a finery of flowers and of vegetables. Or, the reverse side of a coin, as the Mandrake - a plant forming itself in the shape of man. The hand that seems to sprout leaves at its wrist and is used in this book is a pseudo-mandrake - actually a radish. Its nineteenth century engraver, copying a seventeenth century painting of this miraculous radish, was, perhaps, both over-credulous and over- exuberant. Not only are there illusionistic finger joints, but a thumb-nail as well. The World of Wonders, No. 3, also mentions "another radish, exactly resembling a human hand, in the possession of Mr. Bisset, secretary to the museum at Birmingham, in 1802. He declared in his letter that the fingers were quite perfect, and that a large sum had been offered for it and refused."

After Johnson, I wonder if the 1969 Kingsley Amis novel The Green Man, which links the pub name to a sexually sinister spirit called "The Green Man," and further links all that to seventeenth century occultism, suggests that Raglan's idea was known to (and being turned on its head by) Amis.

By the 1970s Raglan's firmly entrenched in the Pagan community...for example Bob Stewart said in Pagan Imagery in English Folksong(1977):

"As a fertility-power, George is known as Jack-in-the-Green, or the Green-man, or Green George...."

The Children's book "The Green Man" by Gail E. Haley (1979), which is said to be based on a mythical English figure of the same name, seems promising, but I don't have it.

That should give you some books to chase down!