In 1721, the smallpox virus was spreading rapidly through Boston, ultimately infecting nearly half of the city’s 11,000 inhabitants and claiming the lives of some 850 people. Many Bostonians survived the deadly virus thanks to variolation, a method of deliberately infecting individuals with small amounts of smallpox pus through cuts in the skin or nasal inhalation.
While the New England preacher Cotton Mather, a prominent figure in the Salem witch trials, has largely been credited with introducing the process of variolation to the colonies, it was actually an enslaved West African man named Onesiumus who instructed Mather on this procedure. Although Onesiumus was not credited with the discovery publicly, Mather disclosed in a diary entry that it was in fact Onesimus who first suggested this method. Variolated against the virus in West Africa, Onesmius shared the knowledge that intentionally infecting a healthy person with a small amount of smallpox pus from an infected patient was a common practice that helped stave off a deadly infection as the body built a resistance to the disease. Onesimus’s knowledge of smallpox led to one of the first known inoculation campaigns in American history, according to a journal article in BMJ Quality & Safety.
Successful variolation treatments had also been achieved in Turkey, China and India by 1721. Lady Mary Wortley Montague is largely credited for bringing smallpox variolation to Great Britain after she learned of the medical therapy in Turkey.
Although Onesimus’s medical experience saved countless lives during the Boston epidemic, he was omitted from medical history for centuries. In 1932, during a speech to the Massachusetts Medical Society, Dr. Samuel Bayard Woodward announced that the idea of variolation “came then from Cotton Mather and from Cotton Mather only.”
Today, there is a movement among historians of science to confront the erasure of these contributions — especially among historians of color who have long fought to correct public understanding.
“I would say that one thing to learn from Onesimus’s story is that medicine advances thanks to the knowledge, labor, and experience of people that often go unrecognized due to racial and other biases,” Reed College history professor Margot Minardi told NBC Boston.
While Onesimus introduced the process of variolation to the Americas, many students are not aware of the history of Onesimus, or the role that enslaved Africans played in shaping early modern science in the Americas.
In contrast to math and reading, there are no nationally agreed upon content standards for teaching social studies and United States history. That means that every state teaches the history of slavery differently, and what public school students do learn is largely influenced by where they grow up.
“One of the things that I hear frequently from undergraduate students is that they feel lied to,” says Carolyn Roberts, a professor and historian at Yale University who researches medicine and slavery in the Atlantic world. “They want to know why they didn’t learn about this history earlier, and the different influences and people who contributed to science.”
In an effort to develop a baseline understanding of how slavery is taught and what is learned in the United States, the Southern Poverty Law Center examined 12 widely used U.S. history books and conducted surveys with more than 1,700 history teachers and 1,000 high school seniors. Their findings revealed that many educators are not sufficiently equipped to teach the history of American slavery, with over 50% reporting that their textbook’s coverage of of the topic was inadequate.
“The best textbooks maybe have 20 pages, and that’s in an 800-page textbook,” Maureen Costello, director of Teaching Tolerance, a program at the Southern Poverty Law Center that promotes diversity education, told The New York Times Magazine. “At its best, slavery is taught because we have to explain the Civil War. We tend to teach it like a Southern problem and a backward economic institution.”
Onesimus’s story raises an important question about our understanding of the history of science in the United States: What kinds of medical and botanical knowledge did African and African-descended people possess, and how did they contribute to early modern science? Even as they were brutally forced from their homelands, enslaved Africans passed on valuable medical knowledge in Britain, Europe, and the Americas.
“African Indigenous medicine is one of the most well developed medical systems in the world, along with India and China,” says Roberts. “People don’t know this when they think about Africa, they think of medical humanitarianism, but 80% of people around the world use traditional medicine.” (Indigenous medicine in the Americas has also had a significant influence on global medical knowledge.)
According to documents sent to the Royal Society, a “Mr. Floyd” and a “Mr. John Smyth” served as ministers at Cape Coast Castle in what is now Ghana, overseeing the enslaved people who were held in dungeons prior to being transported to the Americas. As the life expectancy for Royal African Company employees was just four to five years, the ministers were also searching for traditional methods to minimize deaths and improve the health of employees, while also searching for new botanicals for commercial drugs.
Henry Oldenburg, a scientific correspondent for the society was particularly interested in the “diseases ye Inhabitants are most subject to” and what medicines they used to treat these illnesses. He also wanted to know what poisons and antidotes West African healers used, and what tree bark kept their teeth healthy and white.
John Smyth described how he observed the anti-inflammatory properties of the “unnena plant” which could be boiled and then applied to swollen body parts to decrease water retention. Both palm oil and palm wine were used for a variety of purposes. Palm wine could be mixed with boiled unnena plants to ease constipation, and ointments could be derived from pounding the plant’s leaves and mixing them with palm oil to treat sores and wounds. It was from the enslaved Africans that Smyth also procured a treatment for dysentery by pounding, drying, baking, and consuming the “pocumma plant.” Treatments for stomach aches, smallpox, worms, venereal disease, toothaches, scurvy and hemorrhaging were among the lengthy list of cures Smyth learned from West African experts, according to Roberts. However, the names of the West African botanical and medical experts who informed the minister’s correspondence are absent from these accounts to the Royal Society.
The flow of Indigenous knowledge from Cape Coast Castle to the Royal Society would continue for more than a century, noted Roberts. West African medical practices were of primary importance to James Phipps, chief merchant at Cape Coast Castle, in his writings to his London employers: “We should be glad to have the assistance of an able Gardener, one that is well acquainted with Herbs, as we believe there may be many Simples found here, of very great benefit, being observed to be made use of by the Natives in Pharmacy, as well as Surgery and who succeed in many good Cures in both.”
“The violent trafficking of millions of African people to the Americas has left our world with legacies we are reckoning with today,” Roberts wrote in a blog post for the Royal Society. “One such legacy is the lack of historical acknowledgement of West African people as scientists, botanical experts and medical practitioners, despite their presence in the archives.”
In the book “Bitter Roots” Abena Dove Osseo-Asare describes how for over a century, conflicts over rights to medicinal plants found in African countries have existed between healers and scientists.
“Specifically new medications made from rosy periwinkle, Asiatic pennywort, grains of paradise, Strophanthus Crytolepis, and hoodia,” writes Osseo-Asare. “Some of the pharmaceuticals have been profitable, most have led to patents, and all have resulted in controversies among the many people who have claimed rights to the plants and their biochemical constituents.”
While past historians neglected the stories of enslaved people like Onesimus and the West African botanical and medical experts of Cape Coast Castle, there has been an increase in journal articles and news coverage around Onesimus’s contributions, with Boston Magazine naming him one of the 100 best Bostonians of all time.
“I think that educators can begin teaching these histories from a very young age, and talk about stories like Onesimus’ so that children will be able to see themselves as scientists,” says Roberts. “One of the ways that can happen is by understanding that they, the Black students, are part of a long legacy of healers.”