I’m not a huge fan of Ambrose. I would go with Hastings’ Inferno. As far as the run up to WWII there is nothing specifically for that comes to mind. From a British perspective I like Lynne Olson’s Troublesome Young Men, about how Churchill came to be selected as PM. There is also Tim Bouverie’s Appeasing Hitler: Chamberlain, Churchill and the Road to War. From a German perspective Richard Evans’ The Coming of the Third Reich is fascinating. Have you read William Shirer’s The Rise and Fall of the Third Reich. Read it years ago. Worth a read.