I read a great deal of and about John Cowper Powys (1872-1963), especially, in the 2000s - although I came nowhere near reading all of his output.
I first became aware of him back in the 1970s, when browsing the unusual novels in the Picador Books rotating stand which was to be found in most booksellers of that era. The titles were intriguing to me because Powys came from Somerset (where I spent all my schooldays) and his best novel was set in Somerset - and the blurbs heaped lavish praise on the content - but the length and (when sampled) glutinous density of he prose put me off actually reading anything.
Anyway, sometime later I came across, read, and re-read, Powys's best book (for me) which is his Autobiography. A weirdly mannered, selective (no women mentioned by name) and self-consciously crazed account of his weird mental life. This was written when he lived in upstate New York, at about the same time as he wrote his most admired novels.
I subsequently read those novels, or, at least, I sampled extensively throughout most of them. I would say that his novels are almost unreadable in the normal way (i.e. read from start to finish and missing nothing out) and indeed seem not to require to be read in the normal way.
I don't think the novels were written like normal novels - they were poured-out serially and unrevised and unstructured - in a solitary and solipsistic trance. Their meaning comes from the very broad sweep and from the vastly-detailed scenes - which pulsate with LIFE, and where the protagonists are feverishly aware of the micro-minutiae of their environment. These are unique and characteristic - and they are why I read Powys.
The nearest equivalent in my experience is Women in Love by DH Lawrence; but Powys is even more animistically-detailed while Lawrence was a far, far better craftsman - and Powys has the faults of Lawrence (in structure and pacing and looseness) amplified by an order of magnitude. Powys also has the major fault of Charles Williams: you cannot follow what is going-on, who is doing what, who is speaking etc.
I moved on to read most of Powys's non-fiction books - his popular philosophy (which are easier to read than the novels, and depict the rationale behind the way he wrote) and the available secondary literature of biographies, lit crit, memoirs etc up to the definitive account of Morine Krisdottir Descents of Memory published in 2007.
It is clear now that JC Powys was one of the weirdest men ever to publish zillions of words of writing. On the one hand, he was innately peculiar - a mass of obsessions, compulsions, tics, perversions, habits and hobbies, illnesses and self-indulgences. On the other hand, this natural weirdness was deliberately exaggerated as his way of psychological survival and getting on in the world.
For his early and mid adult life he was a barnstorming, travelling popular lecturer on literature and philosophy (mainly in the USA) - drawing large and loyal crowds - an self-consciously developing an genius persona by lecturing in a wild gestural style in his Cambridge gown, and hamming up romantic eccentricities of dress. On the other hand, this seems to have been the only way he could cope with life - he certainly found life very difficult on a day to day, hour to hour, minute to minute basis - always feeling in danger of being utterly overwhelmed.
He was tortured by duodenal ulcer pains, hours a day, every day, and quite naturally this came to dominate his life and routine - while also being something he exploited in a perverse kind of way.
Perhaps uniquely, it was in his late middle age that Powys began writing seriously, and his vast literary output is essentially that of an old and sick man.
So, why did I read him? The reason was philosophical/ religious. More than almost anyone I can think of, Powys tried to intuit, devise and live-by his own religion - this religion was almost wholly personal and subjective. He didn't seriously expect it to be of much use for other people - although he does outline it as a possible strategy in some of his non-fiction.
This religion was a combination of animism and totemism - everything was alive, everything significant - but some objects (stones, trees) were (literally) worshipped by means of improvised and repeated rituals; while other objects (e.g. his walking stick) were accorded fetichistic significance - and treated with an obsessive solemnity. All about him - people, places and things - were re-named and assembled into a myth which only he knew.
Did it work for him? To some extent it did - it kept him going, and writing; although at the cost of him becoming crazier and crazier, more and more helpless, until he would have struck most people as literally psychotic.
In another sense it did not work - because he was always aware that the structure of interpretations, the sacred objects and rituals, were dependent upon himself - so there was a constant need for energy, focus, creativity to sustain this 'life illusion' as he candidly called it.
And he always remains in a state of desperation - clinging on in the face of the hourly avalanche of difficulties and problems (bad in themselves and further exacerbated by his own decisions).
So - have put you off yet?
If despite everything you want to sample this weird genius, then I would suggest looking at three books: The Autobiography, where you can get to know him on his own terms; Wolf Solent which is the most understandable of his great novels, and the vast and sprawling A Glastonbury Romance which is by critical consent (although the author would have disagreed) his magnum opus.