In 1787, Richard Allen and Absalom Jones founded the Free African Society to support Black Philadelphia residents. Just a few years later in 1793, an epidemic of yellow fever descended on the city. Yellow fever is caused by a virus spread by mosquitos, but at the time, it was ascribed to miasma or contagion among people. Treatments included bloodletting, cold baths, chewing garlic, and drinking whiskey.
As yellow fever began ravaging Philadelphia, people were dying by the dozens daily. With much of the city's officials and the wealthy fleeing the contagion, "there were not enough people willing to tend to the sick or bury the dead," says Barnes.
Rush put out a call for help from Allen and Jones and their Free African Society, in part because he and others believed Africans were immune to yellow fever, says Gamble. This theory was integral to a broader view of black bodies that was used to support slavery—that they were less susceptible to certain illnesses.
The Free African Society was established to help blacks, not whites. And yet Allen and Jones answered Rush's plea. "They wanted blacks to take care of their white brethren so they'd be seen as human beings," says Gamble.
Their efforts did not pay off in goodwill. Read what happened at Smithsonian.