[foobarian]

I think the nationalism was always there in the serf/laborer class. But it was only in the 19th-ish century that firearms started to become widespread so the power gap to the warrior/vassal class closed. Before that the aristocratic layer seemed more disconnected from the lands. Also there is more visibility due to printing, rise of the middle class, etc.

[alternative_a]

We can’t know for sure (can we?) because that class didn’t document. But there are songs and related matter I suppose.

I don’t find the idea that the serf/laborer class harbored “nationalist” thoughts to be very convincing, tbh. Conceptually, the critical attribute is group identity. For that class, religion definitively provided that (supporting proof being the European religious wars) but I wonder if non religious identity extended beyond the village or maybe guilds for the skilled laborers. In each of these cases, there is a structural basis for affinity — one being faith and the other profession.

In general, I wonder if there is any historical basis to the idea that nationalism was an artificial intellectual concept that later infected the general population. Also important to note we should distinguish patriotism (broadly read as support for the sovereign system) from nationalism. The latter more typically is suppressed by patriotic elements in any given society as national boundaries and political boundaries rarely are coincidental.

[foobarian]

It's hard for me to visualize a world where lines of communication were as narrow as back then. The point about group identity is great; what if the Serb village over here in the north had no or very vague idea about all these Serb villages in the south; or had no idea how many total Serb villages there were altogether? But once publishing and communication took off, perhaps people became more aware of the extent of the group and they coagulated. Germany is also a great example, starting from dozens of little states.

[alternative_a]

I can see that in urban environments and in the country cathedral and university towns also could provide information outlets. I know too little about German history to pretend to informed commentary :) but my sense of it is that the emergence of the German nation was a project that had multiple dimensions of support in society, including the nobility and the clergy. It also happened post Napoleon (occupation in parts) and that definitely may have helped gel latent ethnic affinity between the various German principalities.

But I return back to my earlier comment about songs and proles. An expert in 17th century folk songs of European people can shed light on what preoccupied the minds of the lower classes. I sincerely doubt it was ethnic fervor.