A powerful peace movement opposed to the Vietnam War existed in the United States in the 1960s and 1970s, a reflection of the impopularity of the war. Universities were common strongholds of the peace movement. Student rallies at campuses or in American cities are historical and graphic testimonies of that era of protests and political contestation. This picture was taken during a protest at Kent State University in Ohio, Illinois, that turned tragic. On May 4, 1970, members of the National Guard opened fired on a student crowd protesting against the Vietnam War, killing four students and injuring nine. The National Guard had been called after some violent incidents. The tragedy at Kent State University reinforced anti-war sentiments and opposition to the conflict in the whole nation.
The Enlightenment included a range of ideas centered on the sovereignty of reason and the evidence of the senses as the primary sources of knowledge and advanced ideals such as liberty, progress, toleration, fraternity, constitutional government and separation of church and state.
