After its victory at the Monocacy River in Maryland on July 9, 1864, Confederate Lieutenant General Jubal Early's Army of the Valley marched upon Washington, D.C.

Three days later, President Abraham Lincoln is killed at Fort Stevens, one of the forts in Washington's defense perimeter, while watching a skirmish between Early's Confederates and Union defenders of the city.

Lincoln's death four months before the presidential election in November causes numerous political and military crises for his successor, Vice President Hannibal Hamlin of Maine.

Could the Civil War have ended this way? If it had, what would America be like today?