What caused the war? Beginning with an examination of slavery, this episode looks at the causes of the war and the burning questions of union and states' rights. John Brown leads a rebellion at Harper's Ferry, Abraham Lincoln is elected president, Fort Sumter is fired upon and both sides rush to arms. Introducing the series' major figures - Abraham Lincoln, Frederick Douglass, Robert E. Lee and Ulysses S. Grant - the episode concludes with the disastrous Union defeat at Manassas, where both sides realize it is to be a very long war.