Ok so I gotta play along with this a bit.
Michaerl Sharra, born 1916 (death irrelevant). His claim to fame was writing about the American Civil War.
But clearly he wasn't even alive during that conflict, so how do we know his writings are accurate? He's only re-writing/interpreting previous reports on any of the Civil War history. All anecdotal, even if his writings are well done.
Even if he had been alive during the civil war, that still doesn't guarantee accuracy, only his interpretation of what was going on. No one could be everywhere at any given time so they do not know it all personally and must rely on others to fill in the blanks.
Remember, there's 3 sides to every story, and its up to the reader to gather as much information on the subject and then form an educated opinion on it.