Re: Germany? I thought it was Japan
Actual reader of the book here: +1 Mr. D. The Wiki article also gets it right for anyone interested in High Castle's backstory: nearly all of the novel takes place in an alternate history Pacific States of America (Alaska, California, Hawaii, Oregon, parts of Nevada and Washington), within victorious Japan's post-war Greater East Asian Co-Prosperity Sphere. The finale takes place in the Rocky Mountain States, a buffer region between the PSA and the remaining USA, which is a Nazi puppet state a la Vichy France ... with the Missisippi River as the Berlin Wall-esque divide between PSA/RMS and post-war USA. The Nazis (roughly) reprise the U..S.S.R's role in the Cold War; Japan approximates the USA's. The only Nazi-related characters of any consequence are covert Nazi agents, operating in the PSA's proto-Japanese/American hybrid society that was to be explored further in the aborted "High Castle" follow-up novel, "Ring of Fire".
One of the book's core narrative elements (Operation Dandelion) is a preemptive Nazi nuclear strike on the Japanese Home Islands. The Nazis have hydrogen bomb technology and the ability to wipe out the Home Islands. And the will to use it, depending on who emerges as Hitler's successor, who has just died as the novel begins.
Dick was turning American history inside out to try and come to grips with it: for example, with the exception of a small resistance movement, the role of non-Japanese in the PSA is pretty much that of the Native Americans in "our" world, a far cry from today's cliche Merkin. As portrayed in the book, the PSA is a much humbler and an often-saner place than most of the rest of the former USA, perhaps even arguably the "real" USA.
I have no clue what the series will do with the book's story line, but in my opinion it's Dick's finest novel and is a much more thoughtful read than the buzz around the upcoming series might lead a casual reader to believe. Anyone who enjoys it might also appreciate his Vietnamese reprise of the alternate post-war history genre in "Faith of our Fathers", whose main theme is literally (yes, literally) indescribable.