Every now and then I get asked for recipes or information about medieval cooking outside of Europe, and each time it happens I end up mulling it over for days trying to work out an answer. I suppose I could say that I focus on Europe (and sometimes I do), but that answer is an evasion. It doesn't address the question of why I don't research medieval cooking from other cultures.
The first problematical point rests in what is meant by "medieval". Webster's defines the word as "of, relating to, or in the style of the Middle Ages," and goes on to define the middle ages as:
"... the time in European history between classical antiquity and the Italian renaissance (from about 500 a.d. to about 1350): sometimes restricted to the later part of this period (after 1100) and sometimes extended to 1450 or 1500."
This goes back to the origin of the word, which is from the Latin
medium aevum - the middle age, or the time between the classical era and the Renaissance, and most definitions I've seen of "medieval" look something like this.
Europe during this time period had a surprisingly consistent culture. Yes, there were stylistic and political differences for different regions and countries within Europe, but there was also an amazing degree of uniformity in terms of technology, clothing, and (most significantly) food.
These definitions are rather Roman-centered. They clearly make sense when applied to Italy: it's the time between the fall of the Roman empire and the Renaissance. With the extension of years they also make sense when applied to northern Europe (England, France, etc.) as it took much longer for the Renaissance to percolate that far north. It's a bit of a stretch to get it to mesh with places on the edge of Europe though.
When someone then asks about cooking in medieval Japan (or China, or India, or Central America, etc.) I'm first stuck trying to figure out what "medieval Japanese cooking" means. Are they asking about Japanese cooking between the years 500 to 1350? What about 500 to 1500? Maybe some other date range? To the best of my (limited) knowledge of Japan, there isn't that much difference in the culture and cooking in Japan between 1000 and 1800, so just where is the dividing line?
Now if they asked about cooking in "feudal Japan", or "India before the British empire", or "pre-1500 Central America," those are concepts I can deal with. Of course my answer would simply be something like "I just don't study that." I also suspect that answer would be no more surprising than the response to a car dealer's response to "Why don't you sell bicycles?"
It's not that I don't like Chinese or Indian or other cuisines - as my somewhat padded outline will attest, I like a wide variety of foods. It's not even that I don't like the history of the other places. It's just that medieval European cuisine is, in itself, a distinctive cooking system, and since I don't have time to research everything about food and cooking to any real depth, I choose just that one part.