However I think you're missing one of the points of teaching history in schools, which is to instill some sort of shared sense of national identity (which is mostly made up).
I'm Italian, and we are taught that there is some kind of common thread between Caesar, Dante, Machiavelli, and modern Italy. What if we were taught that the durum wheat we use for pasta came from North Africa, that the same idea of making pasta is probably Chinese (by way of the Mongols)? Most of what we consider staples nowadays are either very recent inventions or come from immigration and interaction with our neighbors. How could we justify closing our borders to the refugees coming from the other side of the Mediterranean if we didn't believe the nationalist propaganda?
Another great example of the political use of cuisine is the adaptation of Greek moussaka from its Ottoman ancestor, which involved adding Béchamel to make it more French...