(click to enlarge)
If Britain Had Fallen by Norman Longmate (1972)
Historical 'whatifs' are a favourite staple of novels and stories of course... but the speculation doesn't always involve fiction as such. And one of the favourite 'what if' areas is of course WW2 and how it might have turned out differently...
This book, a relatively early entry in the serious side of the field (it was first published in 1972) takes the simple, seductively fascinating and terrifying idea in the title, and speculates what it might have been like to actually live in Nazi-occupied Britain, by an author whose writing in and knowledge of the subject of Britain in wartime runs more than deep enough to give credence to his deductions (his How We Lived Then: History of Everyday Life During the Second World War is another book I treasure, with its wealth of detail of the lives and living of ordinary folk). While this book is pure conjecture, it is soundly based on the documentary evidence of the German plans for the UK, and what happened in occupied Europe and especially the Channel Islands. I tend to agree with several reviews I have read that Longmate underestimates the bloodshed and sheer brutality that would have been as much a part of this occupation as it was for, say, Denmark, but one can't help but be drawn in by the wealth of detail and intelligent use of source material.
And it is a good read, too :) The genre may be somewhat saturated now - both in fiction and nonfiction - but this one holds its own because of the depth and detail, and is great nightmare fuel for the imagination.