Book excerpt: Lovers of historical fiction will find much to ponder in the 1863 Confederate siege of Knoxville, Tennessee. President Lincoln considered Union victory there a key to winning the Civil War. The siege and its battle of Fort Sanders involved some of the war’s most famous personalities and units. They are brought to life from available histories, diaries and memoirs: Gen. James Longstreet (Gen. Lee’s “Warhorseâ€) and his First Corps of the Army of Northern Virginia—including Barksdale’s Mississippi Brigade, and Parker’s Boy Battery of the Sixth Virginia Artillery. Gen. Ambrose Burnside, whose Ninth Corps hopes rested with Lt. Samuel Benjamin’s Second U.S. Artillery, and the Seventy-Ninth New York Cameron Highlanders. At stake: Control of the Smoky Mountains railroad hub which produced rifles, ammunition, and clothing for the Confederate armies. Could the Union keep it when the ragged and starving Rebels outnumbered them ten to one?