I've been aware of this book since I inherited a copy from my Great Uncle - a life-long resident of Dover. May family ancestors are all from the Dover area and this novel gives a wonderful evocation of the town from two centuries ago.
The style of the language is heavy going at first, but stick with it as there are many colourful characters (Valentine Pepper in particular), as well as lots of historical detail, emotion, drama and romance.
Written in 1942 you get a sense of the comparison between the threat of invasion by Napolean and that of Hitler and this gives the novel a kind of nationalistic tang.
Highly recommended!