If you are a new reader of American Civil War histories, let me warn you about the number one problem in the genre: sources. Sources will lie, sources will obfuscate, and worst of all and sources will often say ignorant things. It is truly sad when a gullible reader believes some contemporary source or other without mediation by a trained specialist. Some of the more brazen sources, the ones that openly contradict – even defy – an author's thesis actually have to be escorted out of the pages of a book, lest they disrupt the reading public's enjoyment.

The people contemporary with events of those days were not malicious, necessarily; they simply lacked the benefit of the hard work of thousands of later Civil War historians who made sense out of events. They could not foresee Nevins, Catton, Williams, Williams, Sears, McPherson and the editorial directors of American Heritage magazine settling every single Civil War controversy with finality and elegance. We cannot be too hard on them.

It is thanks to the recent golden age of Civil War historiography that the field has moved entirely beyond sources, making them almost irrelevant. Who could have anticipated such a breakthrough? The great themes, the narrative structures, the insights, the storytelling, depend very little on sources; more about the intuitive application of literary gifts - and about what sounds right and seems right. Yes, there is the odd source that provides a colorful anecdote, or that moves the story (or thesis) along, but we now live in largely a post-sourcing era, one in which, if sources are to be used at all, they must be managed with great care, and vigorously, publicly abused should they step out of line.

I thought of all this while reading an article in which an historian, recounting a letter written by a farmer near Sharpsburg, corrects the farmer's name for a local bridge. This, I thought, is an excellent display of controlling an ignorant and careless source. I then thought of Allan Nevins' masterful editing of the Charles Wainwright's diaries (A Diary of Battle). Anytime Col. Wainwright of the AoP strayed from the American Heritage editorial line in describing events or personalities or in offering opinions, Nevins was on him with an extensive clarifying comment, often sympathetically rationalizing the colonel's lamentable prejudice or pathetic ignorance.

Sources were useful in the earlier, legalistic days of scholarship, when all the evidence was examined and weighed to reach a single conclusion about a single event. Now that the underlying patterns of truth have been recognized and the storylines developed, sources are irrelevant, though some writers still opt to use them. It may therefore be worth reviewing, in the next few days, how some great names in Civil War history master unruly sources – to protect their readers from being misled by the fool's gold of contemporary testimony.