Short answers, pulled from the story.
The history of medicine is the study and documentation of how medical treatments, practices, and knowledge have evolved over time. It is a multidisciplinary field that draws on economics, health sciences, sociology, and politics to understand how human societies have approached health, illness, and injury from prehistory to the present day.
Early medical traditions include those of Babylon, Egypt, China, and India. The Sumerians of Mesopotamia recorded drug prescriptions on cuneiform clay tablets in the 3rd millennium BCE, and ancient Egyptians preserved medical knowledge on papyrus, including the Edwin Smith Papyrus copied around 1600 BCE.
Otzi the Iceman, dated to around 3230 BC, carried what archaeologist Patrick Hunt describes as a deliberate prehistoric medical kit. It included birch polypore fungus, poppy seeds, sloe berries, and sphagnum moss, suggesting sophisticated self-medication thousands of years before written records.
The four humors were blood, phlegm, yellow bile, and black bile, bodily fluids thought to be linked to illness. An excess or shortage of any one was believed to cause an imbalance that resulted in sickness, a theory that dominated Western medicine until the 19th century and is credited to Galen of Pergamon.
Germ theory gradually replaced humorism in the 19th century through researchers including Louis Pasteur, Joseph Lister, and Robert Koch. Koch reproduced anthrax in laboratory animals and reported the tubercle bacillus in 1881, while Ignaz Semmelweis cut maternal deaths in 1847 by requiring physicians to wash their hands.
John Snow concluded that cholera spread through ingestion rather than inhalation, observing in 1849 that its symptoms were vomiting and diarrhoea. After an outbreak had claimed around 500 lives within a month, his insight led to the removal of the pump on Broad Street, after which deaths from cholera plummeted.