What caused African American demographic patterns in the US to shift during world war 1?

During World War I, the African American demographic patterns shifted primarily due to the Great Migration, as many Black individuals from the rural South moved to urban areas in the North and West in search of better economic opportunities and to escape the oppressive Jim Crow laws. The war created labor shortages in northern factories, prompting employers to actively recruit Black workers, which further incentivized migration. This movement not only transformed the population distribution but also facilitated the growth of vibrant African American communities and cultural movements in urban centers.