Louis Pasteur was born in 1822 in Dole, France, the son of a tanner. Trained as a chemist, he began by studying why wine and beer sour. His experiments demonstrated that specific microbes—not spontaneous generation—drive fermentation, a finding with immediate implications for French industry and scientific method.

Pasteur extended germ theory to human and animal disease. He attenuated pathogens to create vaccines, famously treating young Joseph Meister for rabies in 1885 after the boy was mauled by a dog. His work on anthrax and chicken cholera persuaded skeptics that targeted microbes could be defeated through hygiene, heat treatment, and immunization. The process now called pasteurization—gentle heating to kill harmful organisms—grew from his concern to preserve food without destroying flavor.

Partial paralysis from a stroke in 1868 did not halt his laboratory. Pasteur directed the Institut Pasteur in Paris until his death in 1895, training researchers who spread germ theory worldwide. His rigorous experiments and public demonstrations made microbiology a pillar of modern public health.

1. 1822

   Birth in Dole

   Pasteur grew up in eastern France and earned degrees in chemistry and physics at the École Normale Supérieure.

2. 1857

   Fermentation Studies

   Research on lactic fermentation in beer and wine established microbes as the agents of chemical change.

3. 1865

   Silkworm Disease

   Commissioned to save France's silk industry, he identified microbial causes of pébrine and flacherie in silkworms.

4. 1885

   Rabies Vaccination

   Pasteur successfully treated a bitten boy with a series of attenuated spinal-cord preparations, drawing global attention.

5. 1895

   Death in Paris

   He died at the Institut Pasteur, which continues as a leading center for infectious disease research.