Final answer:
The newly emancipated slaves benefited the most from the Civil War religious revivals as the church continued to play a central role in their community, providing self-determination and a promise of freedom.
Step-by-step explanation:
The group that benefited the most from the Civil War religious revivals were the newly emancipated slaves in the southern states of the U.S. The Protestant Evangelicalism movement during the antebellum years had already brought about substantial conversion to Christianity among African Americans. After the Civil War, the church continued to be at the center of the community for the freed slaves, serving as a means to secure self-determination and a promise of freedom.