Linguistic unity or plurality?

Historians mislead us. Massively. Just as film-makers and many novelists do. Take any history book, textbook, monograph or collection of articles, look at any historical film or swashbuckling TV programme, whether it concerns the accession of Louis XIV, the pleasures and problems of Sissi of Austria or the exploits of the pirates of the Caribbean, you will be confronted with a narrative which automatically presents societies in the past as stable, fundamentally united within a dominant culture and, most of all, perfectly monolingual. Each and every inhabitant speaks the same language, uses the same idioms and everyone understands each other. People from Marseilles and from the Basque country are understood in Paris with no problem, Swedes talk directly with Germans, Estonians, Serbs and other peoples they meet during their wars, the Castilians and the Catalans are always on the same wavelength, and the Sicilians seem to have assimilated the language of Dante even before he was born. No dialects or sociolects, except to introduce some local colour by getting a member of the so-called lower classes to speak patois.

This does not concern the effective removal of the linguistic minorities that made up the Austrian, Russian or even German empires, and the British Commonwealth, or the many dialectal variations which in any European country undermined mutual understanding under the ancien régime right up until well into the nineteenth and even the twentieth century.