More than twenty-five years ago, I interviewed a man who was outwardly the least likely candidate to be an expert on anything, let alone a major era of American history. Dean Helton of Powell, Tennessee, was a high school dropout, a former bus driver, and, at the time of our interview, “just” a janitor at the local public high school.  As I got to know him better, however, I realized that he truly was an expert on the War Between the States, particularly of one specific milit