The History of Vaccines
Onesimus, a slave who was given as a gift to the Puritan church minister Cotton Mather, introduced vaccinations to America.
Though Onesimus, is credited with introducing vaccination he is not credited with inventing vaccinations. When he introduced the process he was simply sharing centuries old tradition of inoculation practiced in Africa. By extracting the material from an infected person and scratching it into the skin of an uninfected person, you could deliberately introduce smallpox to the healthy individual making them immune.
Onesimus’ traditional African practice was used to inoculate American soldiers during the Revolutionary War and introduced the concept of inoculation to the United States.