If Ibram Kendi synthesized the history of racism and showed how racist ideas formed to justify the enslavement of Africans, then Katharine Gerbner digs past that to show how Protestant Christianity functioned as a proto-racial identity to differentiate enslaved people from slaveholders – and how the potential conversion of slaves led to a dilemma solved by the development of racist ideologies.
Gerbner's book doesn't complicate the history of racism and slavery so much as highlight how religion was essential to those things. She shows how in the Caribbean in the 1600s, "Christian" was juxtaposed with "Negro" to create what she calls Protestant supremacy, which which Protestantism was considered equivalent to freedom and self-determination. But when Black people began claiming Christianity, too, Protestant supremacy in the early 1700s shifted into White supremacy, with Whiteness now serving as shorthand for freedom.
Gerbner also shows how Protestant missionaries – Quaker, Anglican, Dutch Reformed, Moravian – were so eager to evangelize among the enslaved that they were instrumental in the creation of a proslavery narrative that discounted the ability of baptism to grant freedom and led to numerous laws throughout the Atlantic world that explicitly disconnected baptism from manumission and instead centered race rather than religion as the signifier of enslavement.
While its arguments are compelling and eye-opening, the book itself gets dry in places, and as a scholarly work, it does a lot of the "set up-tell-conclude" style that feels redundant if you're trying to read for pleasure. But it's not boring, and the story it tells is deeply important. It's easy to assume Christianity was split between people who used it to justify slavery and "real Christians" who opposed it. Gerbner complicates this narrative by showing how planters opposed the evangelization of the people they enslaved; rather, it was Christians who were instrumental in propping up the slave system so their missionaries could gain access to plantations without threatening the planters' livelihood.