The oldest medical text is a clay tablet from Ur from about 4000 years ago. The Kahun papyrus was written in Egypt about 150 years later. There are writings of Hippocrates of Co from about 400 BCE. And then there was Greek and latin medical texts, and those flourished, and the result is that we have a pretty good idea of what medical thinking was like in the mediterranean from an early date.
But what about the other cultures? Well, prior to around 1100 CE, there isn’t much north of the Alps. Well, there isn’t much for all the cultures except for one. The Anglo Saxons. They wrote texts on medicine in both their native language as well as latin in the tenth century and beyond, and we have quite a few that have survived! That alone should tell you how important medicine was to these people. We have lost many manuscripts over the years, so to have over a thousand pages of medical matters written in Old English, and considering how difficult it would have been to produce those texts and preserve them, it shows how serious the business of medicine was to these people.
And here’s the kicker, scholars argue that the older copies have been lost and that the Anglo Saxons had been writing medical texts in their native language since an earlier time.