America 's isolationist philosophy after World War I gave rise to a xenophobic feeling across the nation . This was concentrated in rural areas and especially in the Southern United States and Indiana , where the Ku Klux Klan gained widespread support and sought to persecute immigrants and minorities in the 1920s . At the same time , communism was still a new philosophy in government , and much of the general American public held a hostile view toward it , especially after the 1919 United States anarchist bombings . The beginning of the 1920s saw the height and fall of First Red Scare as exemplified in the trials of Sacco and Vanzetti . This opposition to communism was caused by the bloody terror of the Bolshevik Revolution
1919 United States anarchist bombings
1919 United States anarchist bombings
Social issues of the 1920s in the United States