And All The King's Men is a novel by Gordon Stevens which was kindly recommended by Felix in a comment on my Operation Sealion reading list post.
The story covers the period up to and beyond a successful invasion of Britain in 1940. Whilst there are a few passages in the book which don't flow as well as I might like the overall storyline is engaging and the tale moves along at a brisk pace. As with all alternative fiction there are places where you could question the credibility of some of the plot devices but if you are prepared to do a little suspension of disbelief (this is alternative history and fiction after all!) it makes a ripping yarn.