The process of inoculation against diseases like smallpox has been known for at least 1200 years. An 8th-century Indian book contains a how-to chapter on smallpox inoculations. Chinese use of the technique dates back to the first millennium as well. The technique was imported to Europe via the Ottoman Empire in 1721 and reached America at about the same time.
The practice is documented in America as early as 1721, when Zabdiel Boylston, at the urging of Cotton Mather, successfully inoculated two slaves and his own son. Mather, a prominent Boston minister, had heard a description of the African practice of inoculation from his Sudanese slave, Onesimus, in 1706, but had been previously unable to convince local physicians to attempt the procedure. Following this initial success, Boylston began performing inoculations throughout Boston, despite much controversy and at least one attempt upon his life. The effectiveness of the procedure was proven when, of the nearly three hundred people Boylston inoculated during the outbreak, only six died, whereas the mortality rate among those who contracted the disease naturally was one in six.
It is inadvertently affirmed in the Christian countries of Europe that the English are fools and madmen. Fools, because they give their children the small-pox to prevent their catching it; and madmen, because they wantonly communicate a certain and dreadful distemper to their children, merely to prevent an uncertain evil. The English, on the other side, call the rest of the Europeans cowardly and unnatural. Cowardly, because they are afraid of putting their children to a little pain; unnatural, because they expose them to die one time or other of the small-pox. But that the reader may be able to judge whether the English or those who differ from them in opinion are in the right, here follows the history of the famed innoculation, which is mentioned with so much dread in France.