至於美國的國內事務，年輕的美國民眾對戰爭感到相當厭煩。婦女正行使剛剛取得的新權利 (1920年得到的投票權) ，而許多白人也開始對非裔美人的文化感到興趣。哈林區的夜總會越來越熱鬧，舞台上的聚光燈照耀著許多爵士音樂家，例如路易斯‧阿姆斯壯，以及杜克‧艾林頓等人。

Foreign affairs (relationships with other countries) took up a great deal of President Woodrow Wilson's attention. In Europe, there was the outbreak of World War I, also known as the Great War, in 1914, and in Mexico, there was the Mexican Revolution. Although at first Americans did not want to get involved, they supported the Allies in their fight against Germany, Austria, Hungary, Bulgaria and Turkey. Finally, the U.S. entered the war in 1917. The war concluded in 1918 and the Treaty of Versailles was signed in 1919. The Allied Powers of the U.S., Great Britain, Japan, Italy, Russia, France, Belgium, Serbia and Montenegro had been victorious.

Back at home, young people were tired of the war. Women exercised their newly found freedom (having won the right to vote in 1920) and many whites took up an interest in African American culture. Harlem nightclubs thrived, spotlighting numerous artists such as jazz musicians Louis Armstrong and Duke Ellington.