The Artist in Treason by Andro Linklater

The link I have posted is to an article in the New York Times by Gordon Wood (who is the only History professor I ever had--what my education lacks in depth it makes up for in quality). Wood compares two recent biographies, one of George Washington, and this one of James Wilkinson. The era of early American history is the area of expertise for Wood, so when he calls this the best available biography of the finely feathered general, he know what he is talking about. He also calls it a good read.
I picked this up when I heard the author speaking about it on NPR. Wilkinson was on the Spanish pay roll as a spy for much of his adult life, and it was curiously well known that he was either a spy or a double agent. He lived in the Louisiana purchase, where apparently allegiances were shifting at best and mixed at worst, depending on who controlled the territory. Wilkinson was a decorated Revolutionary War hero, a vain and pompous man who was a disaster at business, and so needed to become a spy to support himself in the style to which he had become accustomed. He was tried for espionage several times, and used his charm and the usual weakness of the case against him to elude legal ramifications. He even encouraged Spain to stop Lewis and Clark, giving up their route westward so they could be intercepted. Fortunately, his talent as a spy did not appear to eclipse his talent at taking care of himself. The book is largely a good read--it is slow in places, occasionally shifting back in time, which is confusing, but overall I would recommend it.