On November 19, 1863, President Abraham Lincoln spoke at the dedication of the national cemetery at Gettysburg, Pennsylvania. The orator of the day was Edward Everett, a famed speaker, former senator, and candidate for vice president in 1860. Lincoln received a late invitation to make "a few appropriate remarks." Lincoln's brief Gettysburg address became a cornerstone of American expression of the nation's ideals, mission, and patriotism.

On the first three days of July 1863, the Army of Northern Virginia, commanded by General Robert E. Lee, had fought the Army of the Potomac, the principal northern army, to which General George G. Meade had been assigned command only four days earlier. In early May, Lee had won a smashing victory at Chancellorsville, Virginia, over a Union force approximately twice as large, then had boldly determined to carry the war to the enemy by invading Pennsylvania. Drawn into an offensive battle at...