Answer:
The Great Migration was the major historical backbone of the Harlem Renaissance. Sure, slavery and the Civil War were important too, because without those two things, people wouldn't have wanted to flee the South in the first place.
But in terms of immediate historical relevance, the Great Migration really made the Harlem Renaissance happen. See, during World War I, job opportunities opened up in northern factories. (There's really nothing like a world war to increase employment.) So, African Americans migrated from the South to the North—especially cities like New York City.
And the war provided them with profitable jobs, which meant they had money to spend. Even more importantly, these new northern immigrants were interested in the hope of a new life and a new racial identity, away from slavery's stranglehold on the South.
All in all, then, the Great Migration allowed for a critical mass of black people to create the major creative movement we now know as the Harlem Renaissance. Bam.
Step-by-step explanation: