First Red Scare

The First Red Scare was a period of intense fear of communism and radicalism in the United States, marked by government raids, arrests, and deportations, especially from 1919 to 1920.

Palmer Raids: A series of federal raids in 1919 and 1920 targeting suspected radicals, many of them immigrants. Attorney General A. Mitchell Palmer used them to arrest and deport people during the scare.
Russian Revolution: The upheavals of 1917 that ended imperial rule in Russia and brought the Bolsheviks to power. The Bolshevik seizure of power made communist revolution seem a present danger to many Americans.
A. Mitchell Palmer: A U.S. attorney general from 1919 to 1921 who directed federal raids against suspected radicals. Palmer became the central public advocate and administrator of the federal crackdown.
Civil liberties in the United States: Rights and freedoms protected against government interference under U.S. law and political tradition. The raids made the protection of speech, association, and due process a central public concern.
Deportation: The removal of a noncitizen from a country under its immigration laws. Federal authorities used deportation to expel suspected radical immigrants without criminal convictions.
Bolshevik Revolution: The October 1917 takeover in Russia through which the Bolsheviks established a revolutionary government. Its success intensified fears that radical groups in the United States might imitate it.
J. Edgar Hoover: An American law-enforcement official who led the Justice Department's Radical Division before heading the FBI. Hoover organized intelligence and records used to identify people targeted in the raids.
American Civil Liberties Union: A U.S. nonprofit organization founded in 1920 to defend constitutional rights and civil liberties. The organization emerged from earlier civil-liberties efforts galvanized by wartime repression and the raids.
Anarchism: A political tradition opposing coercive hierarchy, especially the state, and advocating voluntary forms of association. Officials often treated anarchists as a revolutionary threat alongside communists.
World War I: A global war fought from 1914 to 1918, involving the United States from 1917. Wartime loyalty campaigns and repression left a recent precedent for treating dissent as a security threat.

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