On April 12, 1861, Confederate forces attacked Union-held Fort Sumter in Charleston Harbor, South Carolina, ending an excruciating period of uncertainty and marking the start of the most destructive war ever waged on American soil—the Civil War.

To mark the 150th anniversary of the battle at Fort Sumter, historian Ethan Rafuse of the Military History Department at the Command and General Staff College at Fort Leavenworth discusses the events leading up to the attack, the battle itself, and the effect it had on the nation.