Final answer:
African Americans migrated to Pittsburgh during the post-Civil War Era due to push factors like segregation and economic displacement in the South, and pull factors like better job opportunities, higher wages, and fewer restrictions on civil rights in Northern cities.
Step-by-step explanation:
During the post-Civil War Era, African Americans migrated to cities like Pittsburgh in search of better opportunities, a movement known as the Great Migration. The push factors compelling them to leave the South included racial segregation, poor funding for education, and the displacement caused by the invention of the mechanical cotton picker. Pull factors attracting them to cities like Pittsburgh were the promise of higher wages, better schools, the absence of legally enforced segregation, and job opportunities in industries such as steel, mining, and construction. This migration was also fueled by the active recruitment of African American workers by Northern factories, especially during World War I, and the chance for African American men to vote freely and participate in politics.