Onesimus
late 1600s-1700s · Contribution: c.1716-1721
Enslaved man; source of inoculation knowledge
Introduced the principle and procedure of variolation (smallpox inoculation) to colonial Boston — deliberately introducing material from a smallpox pustule into a small skin wound to confer immunity — based on a practice long used in West Africa

Portraits are AI-generated interpretations, not photographs.
Quick facts
- Born
- West Africa
- Active since
- 1706
- Category
- Science & Medicine
- Best known for
- Introducing smallpox inoculation to colonial Boston
Impact on the world
Onesimus brought life-saving African medical knowledge to colonial America, laying groundwork for the practice of inoculation that would eventually lead to vaccination.
Sources
- Smithsonian
1 more sources and references are available to members.
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