In 1721, Boston witnessed a pivotal advancement in public health with the introduction of smallpox inoculation. Promoted by Cotton Mather, a Puritan minister, and Dr. Zabdiel Boylston, this early vaccination method involved exposing a person to a small dose of the smallpox virus to build immunity. Despite initial opposition, this practice resulted in significantly reduced mortality rates and highlighted the potential of preventative healthcare, marking a crucial development in medical science.