I had never heard of Onesimus either. There is a fascinating story about his life in the article below.
Apparently Cotton Mather, a Puritan minister, wrote of him in his diary.
When a smallpox epidemic ravaged Boston in 1721, a doctor named Zabdiel Boylston got the seemingly crazy idea to expose healthy people to small amounts of pus from smallpox patients.
www.forbes.com
When a smallpox epidemic ravaged Boston in 1721, a doctor named Zabdiel Boylston got the seemingly crazy idea to expose healthy people to small amounts of pus from smallpox patients. The healthy people would get sick, but not as sick as if they’d caught a full-fledged case of smallpox, and they would have lifelong protection against smallpox. Boylston called it variolation or inoculation, and he got the idea from Puritan minister Cotton Mather, who used his pulpit and his fame to advocate for the wildly unpopular new preventive measure. And Mather, in turn, got the idea from an enslaved man named Onesimus.
***snip***
Nearly everything concrete we know about Onesimus comes from Cotton Mather’s diary, with a few potential glimpses in later church and civic records. We can say for certain that he was an enslaved person in Massachusetts in 1706, but we don’t know whether he was a new arrival in North America or had been there for some time. It’s almost certain that he was born in western Africa, because he’d been inoculated against smallpox as a child in a traditional West African way.
We know that he joined Mather’s household in December 1706, when the Puritan congregation of Boston’s North Church decided that a live human being would be the perfect gift for their fiery witch-trial-veteran minister, Cotton Mather. And we know, of course, that during the years of his enslavement, Onesimus told Mather about inoculation against smallpox.
Additionally, we know that he had a family, a livelihood, and ambitions of his own. Mather’s diary mentions that Onesimus was married, but doesn’t mention any further details about his wife, and that probably means that she didn’t live in the Mather household. We have no way to know if Onesimus’ wife was also enslaved in another household, or if she was a free woman. In either case, the couple had – and lost –at least two sons. One died in 1714, and another in 1716. Mather refers to one of the children as “Onesimulus,” but it’s likely that the minister was just trying out some clever wordplay rather than using the child’s actual name.
Of course it is Cotton Mather who gets the credit for the idea.
Smallpox raged through Boston in 1721, ending in 844 deaths. During this epidemic, physician Zabdiel Boylston, at Cotton Mather's urging, variolated 248 people, thereby introducing variolation to the Americas. Of those variolated, six…
www.historyofvaccines.org
Smallpox raged through Boston in 1721, ending in 844 deaths. During this epidemic, physician Zabdiel Boylston, at Cotton Mather's urging, variolated 248 people, thereby introducing variolation to the Americas. Of those variolated, six died. The case fatality for variolation was about 3%, and the disease case fatality was 14%. About 900 people left town for fear of catching the disease.
Howeaver if you do a search for Onesimus on that web site you find…
1706
African Use of Variolation
Cotton Mather, a Boston minister (1663-1728), received a "gift" of a Libyan-born enslaved person named Onesimus, who bore a scar from smallpox variolation in Africa. Mather inquired among other enslaved people and found that many had been variolated and thought themselves immune to the disease.
Later, Mather would read of variolation in English medical journals and promote the practice in Massachusetts.