American Renaissance
The American Renaissance was a period of American architecture and the arts from 1876 to 1917, characterized by renewed national self-confidence and a feeling that the United States was the heir to Greek democracy, Roman law, and Renaissance humanism. The era spans the period between the Centennial Exposition (celebrating the 100th anniversary of the signing of the Declaration of Independence) and the United States' entry into World War I.
Harlem Renaissance
The Harlem Renaissance grew out of the changes that had taken place in the African-American community since the abolition of slavery, as the expansion of communities in the North. These accelerated as a consequence of World War I and the great social and cultural changes in early 20th-century United States. Industrialization was attracting people to cities from rural areas and gave rise to a new mass culture. Contributing factors leading to the Harlem Renaissance were the Great Migration of African Americans to northern cities, which concentrated ambitious people in places where they could encourage each other, and the First World War, which had created new industrial work opportunities for tens of thousands of people. Factors leading to the decline of this era include the Great Depression.