I have one nomination to make so far.
Owls Do Cry - Janet Frame.
https://www.goodreads.com/book/show/895005.Owls_Do_Cry
https://en.wikipedia.org/wiki/Janet_Frame
This is commonly regarded as NZ's first true novel, published in 1957, and while it is well regarded internationally in literature it does promote mixed reactions from readers. Frame's own past is troubling and as far as I can gather that is reflected in this book. I have not read any of her novels, just have intended to, except for one of her autobiographies which I read back (way back

) in student days.