This year marks the 40th anniversary of the Attica Rebellion. On September 9, 1971, some 1,200 prisoners at Attica Prison in upstate New York seized control and took 38-prison guards hostage. For four days, the “Attica Brothers” controlled the D-yard. Americans were glued to their televisions as prisoners issued a call to people on the outside to support their stand. The Attica Rebellion was the most well organized prison uprising in U.S. history-people around the world saw the act as a response to inhumane prison conditions.

The key event leading up to the Attica Rebellion was the murder of George Jackson, a Black revolutionary imprisoned in California. As word of Jackson’s murder spread from cell to cell, a plan developed to organize the prison in a united protest of outrage and mourning. The next morning, as the men filed out for breakfast, they organized themselves into two columns, headed by Black prisoners. Inside the mess halls, hundreds of prisoners, including Hispanics and whites, sat in total silence. Wearing black armbands, they fasted, harboring bitter thoughts against the system that had murdered their comrade and subjected them to inhumane prison conditions.

“The entire incident that had erupted at Attica was because of the unmitigated oppression wrought by the racist administration of this prison. We are men, not beasts,” L.D. Barkley told the Revolution News. Barkley has been a spokesman on behalf of the rebellion for 21 years. “We did not intend to be beaten and driven as such. What happened there was the sound before the fury of those who were oppressed.”

Barkley went on to explain how America watched on television as those who had been taught to fear prisoners learned of the organized destruction of the human beings inside the prison system.

“Millions came to know and embrace the humanity and courage of the prisoners, justice of their rebellion and their demands,” he added.

On the morning of September 13, 1971, negotiations broke down. New York Gov. Nelson Rockefeller ordered Attica be taken by force. Tear gas was dropped over the prison and state troopers opened fire on a group of over 1,200 inmates. In the chaos, 10 hostages and 29 inmates were killed by police gunfire. 80 people were seriously wounded, the majority of them inmates, in what was the bloodiest prison uprising in U.S. history.