Final answer:
The Age of Exploration significantly contributed to the Christianizing of Africans as European explorers and missionaries spread the religion. Subsequent movements like the Protestant Evangelicalism during the first Great Awakening and the formation of the African Methodist Episcopal Church were also instrumental in the spread of Christianity among African communities, especially in America.
Step-by-step explanation:
The movement that contributed to the massive Christianizing of Africans was the Age of Exploration. During this period, European explorers and missionaries spread Christianity across different continents, including Africa. This effort was sometimes paired with colonial and mercantile activities, particularly during the Atlantic slave trade, which saw the justification for enslaving Africans partly in terms of exposing them to Christianity. However, it's worth noting that in the case of the enslaved Africans in America, a significant increase in Christian conversion among them happened with the rise of Protestant Evangelicalism during the first Great Awakening.
Additionally, the formation of African American churches, such as the African Methodist Episcopal Church, played a crucial role in establishing a distinct African American Christian identity and community. These developments occurred alongside and after the Age of Exploration and were significant in the spread of Christianity among people of African descent, particularly in America.