One of the original books from the genre of “alternate history” - maybe not strictly scifi, but nevertheless penned by one of the most important SF authors ever.
Don’t expect a huge blast from this book in terms of any battles or other kinds of huge slaughter - it’s a very subtle, quiet book. The basic premise is that Germany and Japan won WWII and sliced the US in half, reduced white Americans to a servants’ caste. The story depicts the rambling lives of several Japanese and German officials who are dealing with the depressing nature of their countries’ victory and some Americans who are trying to bring some light of meaning into that bleak world.