Very useful points of reference, Bill.
By the 1790s there were, in fact, numerous expressions of the nationalist principle in action or nascent, for example in the borderlands between Hapsburg and Ottoman Empires, among the Croats and Serbs. the Vlachs and Bulgars, and of course in Greece. Polish nationalism had expressed itself in rsistance to the successive partitions of the late C18th. We might discuss the United Irishmen movement and, with less conviction perhaps, the relevance of the failed Jacobite risings to a sense of Scottish nationalism. The formation of the Highland regiments in the service of the House of Hanover were served as a contrasting and very successful expression of the Scots as Britons. The French wars also served to generate a renewed spirit of patriotism among the English and a sense of 'Britishness' throughout the kingdom although not distributed evenly amongst all the nations or in every class. The spirit of revolution was also playing its part.
Of course, a newly established nation was knitting itself together out of the former British colonies in North America, and the presence of republican armies in Italy was an expression of the new spirit of La Patrie in France. Meanwhile, proto-Belgian and Dutch nationalists had marched with French armies into the Low Countries intending to forge republican nations in their homelands, although they would be disappointed. Within France itself, regional resistance to the republic might be seen as an expression of a local, particularist nationalism, notably among the Bretons. The later French incursions into the Iberian peninsula would generate a nationalist reaction amongst the disparate elements of Spanish society which combined, briefly, to expel the invader. The paralysis of Spanish Imperial power abroad also led to the independence movements in Latin America.
There are doubtless other examples.