According to the author in his preface, John Deane really existed and had an interesting and successful life in a variety of roles. He was born in 1679, of well-to-do parents, but started his working life as a drover, that is to say a person who drove great herds of cattle from the countryside to the great cities like London, for consumption there. He then joined the Navy and rose to become a ship's captain. After a spell as a Merchant Adventurer, he commanded a vessel in the Russian navy of Alexander the Great. Later he became British Consul at Ostend, on the coast of Belgium, quite close to south-east England. Finally he came back home to live in a village near Nottingham, receiving civic honours in that city. He died in 1760.
This book could therefore be called a historical novel, but written with the style and genius of Kingston it becomes far more than that. You will enjoy it.