Many medieval doctors believed that certain ailments could be treated by exposing the sufferer to different lights and colours. The 12th century writer Hildegard of Bingen, for instance, suggested that those with eye problems could do no worse than spend hours each day staring at green grass. Another prominent advocate of this ‘colour therapy’ was John of Gaddesden (died 1361). Gaddesden was a royal physician to Edward I. His standard treatment for smallpox was to wrap the patient in a red cloth, fill the room with red decor – and provide the patient only with red foods and drinks:
“…Take a scarlet or red cloth be taken and the variolous [pox-ridden] patient be wrapped in it completely – as I did with the son of the most noble king of England when he suffered those diseases… I made everything about his bed red… it is a good cure and I cured him in the end without the marks of smallpox.”
Despite its lack of effectiveness the ‘red treatment’ for smallpox remained in vogue for centuries. Queen Elizabeth I was wrapped in a red blanket when she contracted the disease in 1562. Early modern smallpox wards were outfitted with red walls, red curtains and red lamps. The American colony of Massachusetts passed a law in 1731 requiring “a red cloth to be hung in all infected places”. Even Niels Finsen, winner of the 1903 Nobel Prize for medicine, called for infected patients to be housed in specially outfitted rooms and bathed under red sunlamps.