Medieval Medicine: Beliefs & Treatments c1250–1500
Ideas About the Cause of Disease
In medieval England (c1250–1500), people had very limited understanding of what actually caused disease. Without microscopes or scientific methods, they relied on explanations that seem strange today but made perfect sense within the knowledge available at the time. These explanations fell into two broad categories: supernatural and religious explanations, and rational explanations based on ancient Greek and Roman ideas.
Medieval people explained disease through two main approaches: supernatural and religious explanations (God’s punishment, astrology, evil spirits) and rational explanations (the Theory of the Four Humours and miasma theory).
Supernatural and Religious Explanations
The Church dominated medieval life and taught that God controlled everything — including illness. Many people believed disease was a punishment from God for sinful behaviour. Prayer, fasting, and pilgrimage to holy shrines were therefore seen as logical treatments. Some also believed that astrology influenced health, with physicians consulting star charts before diagnosing patients.
The Church was the most powerful institution in medieval England. It controlled education, hospitals, and most people’s daily lives. Priests told their congregations that illness was God’s will, and few people had the literacy or knowledge to challenge this. The Church also discouraged dissection of human bodies, which prevented people from learning how the body actually worked. With no alternative explanations available, supernatural beliefs went unchallenged for centuries.
The Theory of the Four Humours
The most important rational explanation for disease came from the ancient Greek physician Hippocrates (c460–370 BC). He argued that the body contained four key fluids — or humours — and that illness occurred when these became unbalanced. The four humours were: blood (associated with spring and air), yellow bile (summer and fire), black bile (autumn and earth), and phlegm (winter and water).
This theory was developed further by the Roman physician Galen (AD 129–216), who added the Theory of Opposites. If a patient had too much phlegm (cold and wet), they should be treated with something hot and dry — such as pepper. Galen’s ideas were promoted by the Church because he believed the body was designed by a creator, which fitted Christian teaching. His writings dominated medical training for over 1,000 years.
Galen’s ideas went unchallenged for over 1,000 years. The Church supported his work because he believed in a single creator God, and anyone who questioned Galen was seen as questioning the Church itself.
Miasma Theory
The miasma theory held that disease was caused by “bad air” — foul-smelling vapours that rose from rotting matter, swamps, or human waste. This was a rational explanation because it was based on observation: disease did seem more common in dirty, smelly areas. Although the theory was wrong, it sometimes led to useful public health measures such as cleaning streets and draining marshes. Town authorities occasionally ordered the removal of dunghills and slaughterhouse waste from near homes, believing that eliminating foul smells would stop disease spreading. These measures accidentally reduced some infections by improving sanitation, even though the reasoning behind them was incorrect.
Approaches to Prevention and Treatment
Medieval treatments were directly connected to beliefs about disease. Because people thought illness came from God, the humours, or bad air, they used treatments designed to address those causes. Bloodletting and purging were used to rebalance the humours. Patients were cut to release blood, or given laxatives to purge excess humours. Purifying the air with sweet-smelling herbs and flowers was used to combat miasma. Prayer, attending church, and going on pilgrimages were used to seek God’s forgiveness.
Three main types of medical practitioners existed in medieval England. Physicians were university-trained doctors who studied Galen’s texts — they were expensive and only available to the wealthy. An apothecary mixed and sold herbal remedies, acting like an early pharmacist. Barber surgeons performed basic surgery such as pulling teeth, setting broken bones, and bloodletting — they were the most accessible practitioners for ordinary people.
Most people, however, could not afford any of these. They relied on community and home care — family members (usually women) used herbal remedies passed down through generations. Recipes combined ingredients like honey, garlic, sage, and vinegar. Some of these remedies were surprisingly effective — honey, for example, has genuine antiseptic properties.
Hospitals and Care
Medieval hospitals were run by the Church and staffed by monks and nuns. They focused on spiritual care rather than medical treatment — patients were given food, shelter, and prayers, but rarely received medicine. Hospitals turned away people with infectious diseases to protect other patients. They were small, typically housing only a few dozen people, and functioned more like hospices than modern hospitals.
Medieval hospitals provided care for the soul, not the body. They offered food, shelter, and prayer but rarely treated illness. People with contagious diseases were turned away.