On this day, May 31, in 1921

The little known Tulsa Race Riot erupted in Tulsa, Oklahoma, devastating the prosperous and largely self-sufficient black community of Greenwood. Long-standing racial tension spiraled out of control when a rumor spread that a black man had sexually assaulted a white woman, and angry mobs of white people armed themselves and attacked Greenwood. When the National Guard arrived, they ignored the white attackers and instead forced black people into detainment centers, even using machine guns. When the rioting ended the next morning, many lay dead in the rubble. The death toll was later estimated from 60 to 300, almost all of who were black.