First of all, ... it has nothing to do with American military history, but is a study of the life and writing of a 17th-century English Puritan.
Nehemiah Wallington was a turner (i.e., he made wooden furniture and utensils with a lathe)and second-generation Calvinist who spent his life (1598-1658) within a small area of London. Although he was not famous during his lifetime, he has become invaluable to historians because of the tremendous written record he left behind. In an age when most artisans were illiterate, Wallington wrote over 2,600 pages of diaries, letters, and religious and political essays. These provide a rare window into the life of the common man at the time of the English Civil War.
Paul Seaver offers insightful and often entertaining commentary on Wallington's life -- along with copious excerpts from the original documents -- in a series of thematic chapters dealing with Wallington's religious beliefs, family life, trade, etc.
While Wallington is a fascinating character, it soon becomes clear that he cannot be considered entirely typical of his time. It isn't just that he could read and write, or that he spent his whole life in the same neighbourhood at a time when Britain's population was highly mobile, or that he outlived 97% of the people in his generation. It's obvious from his memoirs that Wallington was mad. In his youth, he had spells of suicidal depression and religious delusions (he once believed that the Devil talked to him for an hour in the shape of a crow). The delusions stopped in his early 20s, but throughout his life he was plagued by recurrent "melancholy" accompanied by religious doubts.
Nor is Wallington always easy to like. He comes across as utterly self-absorbed, and he was fanatical and judgmental to a degree that was probably unusual even among the Puritans of his time. Whenever something bad happened to one of his neighbours, Wallington assumed it was God's punishment -- and he usually knew exactly what sin had triggered it, too.
That said, Wallington is not an entirely unsympathetic character. Though some of his religious agony was so overblown that it can cause nothing but pity, some of the questions that troubled him are the same ones that have troubled believers throughout history. There are also times when he strays from his usual subjects and gives us glimpses of his daily life and family relationships, which let us in on his full range of feelings. His reactions to the deaths of four of his five children are especially moving.
Nor should the turner be dismissed as wholly unrepresentative of his time. Even his most bizarre delusions were heavily influenced by the predestinarian beliefs of his time. As for his self-righteousness and intolerance, they give a taste of the atmosphere which led to revolution and the death of the king.
Seaver does a good job of presenting a character who is unusual enough for a novel, but also indisputably of real life.