On 12 April 1864, Confederate soldiers led by Nathan Bedford Forrest attacked Fort Pillow. Despite being outnumbered three to one, US forces refused to surrender until shortly after 4pm when the garrison was overwhelmed.
A Joint Committee on the Conduct and Expenditures of the War investigated the Fort Pillow massacre, and their findings were reported on by the New York Times in 1864:
The rebels commenced an indiscriminate slaughter, sparing neither age nor sex, white nor black soldier nor civilian. The officers and men seemed to vie with each other in the devilish work. Men, women and their children, wherever found, were deliberately shot down, beaten and hacked with sabres. Some of the children, not more than ten years old, were forced to stand up and face their murderers while being shot. The sick and wounded were butchered without mercy, the rebels even entering the hospital buildings and dragging them out to be shot, or killing them as they lay there unable to offer the least resistance. […] All around were heard cries of “no quarter,” “no quarter,” “kill the damned niggers,” “shoot them down.”
After the war, Forrest went on to become the first Grand Wizard of the Ku Klux Klan. There’s an ugly statue of him outside Nashville, Tennessee.