Final answer:
The material in Alain Locke's book 'The New Negro' first appeared in various publications and is considered a seminal work of the Harlem Renaissance, reflecting a shift in African-American self-perception in the 1920s.
Step-by-step explanation:
Alain Locke's influential anthology The New Negro was first published in 1925 and is often hailed as the manifesto of the Harlem Renaissance. The content in The New Negro initially appeared in various publications and as a concept can be traced back to a term that was in use since the late 19th century. However, Locke's use of the term in the 1920s evolved to delineate a new sense of pride, assertiveness, and demand for respect among African-Americans, pivotal to the Pan-Africanism movement. Writings from this anthology drew contrasts between the 'Old Negro' with the 'New Negro,' emphasizing a cultural shift towards self-confidence and assertiveness in the African-American community post-World War I. Locke's work also encapsulated the struggle for a literary voice that would encompass distinct African themes and styles, diverging from traditional European literary influences, and thereby grounded itself as an emblem of racial consciousness.