Whose discovery was the first vaccine against smallpox?

Edward Jenner, an English physician, made a landmark discovery in 1796 when he inoculated a young boy with material from cowpox lesions and later showed protection against smallpox. This was the first true vaccine and the beginning of modern immunology. Jenner published his findings in 1798, and vaccination gradually replaced older, riskier methods of variolation. Smallpox was eventually eradicated worldwide, declared so by the World Health Organization in 1980. Jenner’s breakthrough remains one of the most important in medical history.