Published posthumously in 1966, this was Treece's finest exploration of aspects of the 'Matter of Britain' (as other later writers have since called such themes), despite much of the action talking place oustide of Albion. It is a stand alone adult novel that he didn't rework for children as with so many of his other historical recreations.
He was always fascinated by what he termed the 'crossroads of history', times of momentous change taking place either through invasion or the assimilation of new cultures and peoples. The Green man reworks the Hamlet story and sets it in its original time, the 6th century CE. Amleth, as our 'hero' is called, makes his physical, spiritual and dynastic journey to meet his destiny in a turbulent and violent era. On the way, he encounters an aged but still very dangerous 'King' Arthur, and a terrifying, piratical Beowulf, neither of whom conform to the normal depictions we are used to. The action is bloody, the characters strong and vivid, the prose is vigorous and poetic as one would expect given Treece's former years working as a poet.
This edition was issued on a Science Fiction imprint, with a suitably racy cover (for its year), but really it is a retelling of our history as it might have been, with a clear sense of myth and ancient beliefs. It is such a pity that none of Treece's novels or volumes of poetry are now in print. Rediscover an overlooked master.