Slavery in America meant enslaved people were treated like products to barter, buy, and sell. The dehumanization of enslaved Africans meant slavery was tolerable, but for Black women's womanhood and feminine identities to be maintained, slavery would have been viewed as vile as it truly was. Thus, the preciousness of the Black woman was stolen as much as possible-- her ability to maintain her motherhood, her personal autonomy, take care of her body, all removed from her reach. Scholarship bent to accomodate racism and medical authorities confirmed false news to keep business running smoothly: that Black women's pain tolerance was higher than that of women of other ethnic backgrounds. If a woman only feels pain at a high tolerance level, her fragility is no longer accessible to her, and a woman's relative softness and fragility on a biological basis compared to the biological makeup of a man is no longer in question. And thus began the myth of Black women's supernatural physicality, likening Black women to animals or to men in their laboring abilities, making raping them and beating them acceptable behavior because although their vulvas were just as satisfiying to a man's body as that of women of other ethnic backgrounds, if they were not really women, was it really rape?
This horrific history led to the on-screen depiction of Black women as "the help," through the "mammy" trope of the kind and submissive assistant to the beautiful leading white lady, visually depicting a parallel between white, healthy, and beautiful, and black, overweight, and unattractive or plain. Further, stereotypes of Black women being the mortar that fills in the cracks of society, picking up loads dropped by others and endlessly willing to self-sacrifice for the "greater good," and the continuation of Black women as the mascot for hypersexualization, poverty, and troublesome behavior in media are contribution factors to why the world still often struggles to receive a feminine, classy Black woman who is taken care of and prioritizes self-care and self-respect.
Check out the resource below for some interesting reading to get your research started.
Caren M. Holmes "The Colonial Roots of the Racial Fetishization of Black Women."