I agree with Andy Cardinal on An End to Innocence: The First Battle of Manassas by John J. Hennessey. I got this years ago because Hennessey did such a great job with his other book called- Return to Bull Run: The Second Battle of Manassas. I second this also with Andy Cardinal on Maps by Gottfried for I have a copy on Maps in Antietam and Gettysburg by Gottfried but not on First Manassas but you can't go wrong with these. A book I recommend is: Battle at Bull Run: A History of the First Major Campaign of the Civil War by William C. Davis. Thank you Andy Cardinal for recommending Early Morning of War by Longacre for I have not read this and checked out the positive reviews on this book at amazon. I'm going to put this on my wishlist.