candidate: Orangeburg massacre ; Orangeburg , South Carolina - February King assassination riots : 125 cities in April and May , in response to the murder of Martin Luther King , Jr. including : * Baltimore riot of 1968 ; Baltimore Maryland * 1968 Washington , D.C. riots ; Washington , D.C. * 1968 New York City riot ; New York City , New York * West Side Riots ; Chicago , Illinois * Louisville riots of 1968 ; Louisville , Kentucky * Hill District MLK riots ; Pittsburgh , PA * Summit , Illinois Race Riot at Argo High School , September 1968