Both the French Revolutionary and Nationalism scholars I've read argue that nationalism originated during the French Revolution. While we have an idea of nationalism that's been established through history, the French Revolutionaries' concept of the "national" would not have the same ideas and implications associated with it today. So, what did they think they were saying when they chose "national." Why not something else?
The concept of « nation » is a difficult topic, and a very debated one in French historiography. It should be the same elsewhere. The first difficulty is as you said (the French Revolutionaries' concept of the "national" would not have the same ideas and implications associated with it today) what definition the words nation and nationalism have. Definitions have changed through time, from before the Revolution to the Revolution and its long history in the 19th and 20th centuries. The second difficulty is that the word nation and the idea behind it is different from country to country. As such, the French nation is closer to the German Volkgeist or the Russian Narodnost’ rather than Nation or natsia but the concepts behind these three words are very different. Firstly, I will explain the different definitions for the French word nation. Then we will see what it meant in 1789 and the following years which should answer your question.
What is the definition of the French word nation?
The word nation is an old world in French. It can be found as far as the 13th century and although the meaning is very different from its modern definitions, it can be enlightening. In the 13th century, nacion/nation/nassion meant a group of people originating from a common place and sharing common interests. As an example, university students during the Middle-Ages were sometimes grouped by nation, students from Picardie would be together. Looking at Frédéric Godefroy who gathered texts from the Middle Ages to create his dictionary of Middle French, the word nacion often means a place of origin (parish, city), probably with a common cultural identity. This is very much looking like the ancestor of our definition of nation.
Now what is still lacking in this definition is the link between nation and power because the late 18th century meaning of nation did link the idea that the nation had the power, the idea of national sovereignty. I am not going to look in all dictionaries from the Middle-Ages to the modern times, but looking at Antoine Furetière’s 1690 dictionary page 157 and the 1765 Encyclopédie of Diderot and D’Alembert we have two useful definitions:
As we have seen, during the 18th century the concepts of nation and State or power are linked. Ahmed Slimani, a law professor, described several uses of the concept of nation in the 18th century. In the fifth paragraph, the author gave various example and depending on the 18th century author, the nation can be the entire society, can or cannot be the same as the State. In short, there were not clear and unique concept of what the nation was but it is possible to draw the conclusion that society (including the people in its entirety), territory and power/laws/institutions are components of the nation. And the embodiment of the nation was none other than the king because he was the father of his people and the source of power. But of course, this view was much more contested during the 18th century than it was before. The Enlightenment political thinking generally called for a non-arbitrary government, where power would not be resting in the hands of a single individual. Plus, Charles-Louis de Montesquieu’s philosophy claimed that the nation was in fact made of the will of the society to live together and this was independent from the will of the State. This view proved to be very popular and helped to define the French nation in the two next centuries. One can see where this is going. With such an idea, the absolute monarchy can no longer work.
The nation by 1789.
During the last half of the 18th century, the history of the monarchy is one of almost constant conflict with the parliaments of the kingdom. The French parliaments were not legislative bodies but of justice. In their struggle with what they called (often in bad faith) the tyrannical and arbitrary monarchy, the parliaments made themselves the “representative of the nation”. Of course, this is not true by our standards, members of parliaments were aristocrats who most of the times struggled with the monarchy to keep their privileges. But what is interesting is that in their struggle, their weapon was to make themselves the link between the king and all his subjects and when necessary, protectors of the subjects/of the nation. For many of the members of parliament, their role was too limited, too reduced while it was they who represented the nation. During the French Enlightenment, many dreamed of a system similar to England, where the power of king (was thought to) belong to the ” nation”, to the Parliament. this, the king is no longer the embodiment of nation.
By the time the Revolution broke out, one of the major debated topic in France was about who represented the nation, who was the nation. Like when the parliaments thought that they should own power because they represented the nation, in the new order that was to be created by the Revolution, the sovereignty was to belong to the nation. In January 1789, Sièyes wrote What is the Third-Estate ? and in the first chapter wrote that the Third-Estate is ”everything” and ”a complete nation”. Sièyes’ vision was adopted like the events proved. If the Third-Estate is everything that matters and a nation by itself, this meant the end of the two other orders (clergy and nobility) and that the power then belonged to the Third. The nation, embodied by the Third also had the sovereignty. No longer the king (even if he remained part of the society until 1792), no longer the other orders, the sovereignty was national. The best example in my opinion of transition from royal/divine sovereignty to a national sovereignty was on the June 17th 1789 when the new National Assembly proclaimed it had the right to decide the taxes. To whom the taxes are paid to is to whom the sovereignty belongs (the fight over taxation was almost an important part of the conflict between monarchy and parliaments).
So, the French nation as created by the Revolution was a mix of new ideas and older concepts. After 1789, the nation was a society of free supposedly equal individuals (citizens) bound to live together because they willed it. What it means is in fact nothing else than self-determination. From there, the French national concept used during the 19th century was born: all can become French if desired. To that end one needs to be included in the French national territory (either by moving or by the voluntarily integration of the territory like with Avignon in 1789). The French language is not an obstacle, because at the time not many French people spoke French and a language can be learned. This is the contrary of the German concept of the nation that started to emerge after the Napoleonic crisis. Fichte or later David Strauss imagined the German nation differently, to simplify, language was one of the most determining factor of who was German and who was not. This participated in the clash between the French and “German” nations over Alsace.
To conclude and hopefully finally answer your question, the use of national in many French institutions (assemblée nationale) or concepts (territoire national) was the way to inscribe within the French consciousness whom was the owner of the authority, that is the Third-Estate which was everything and a complete nation. Since the two other orders were eradicated/abolished, then only one social body of united individuals remained and it was the Third, which was the embodiment of the nation.
I do hope this is clear enough and answers your question. The construction of a national feeling, leading to nationalism later in the 19th century is a complicated subject and I am sure that many disagree with what I wrote depending on which historians they refer to. After all, some historians have claimed or still claim that a French national feeling (or proto-national) exist since the Middle-Ages. If I did not completely answer your question feel free to tell me. Do the same if my English is clunky.
Sources other than the links:
CHALINE Oliver, La France au XVIIIe siècle (1715-1787), Paris, Belin, 2012.
GIRAULT René, Peuples et nations d’Europe au XIXe siècle, Paris, Hachette, 1996.
BIDOUZE Frédéric, « Pour une autre histoire des parlements au XVIIIe siècle : discours et représentations, une culture française du politique » in Parlement[s), Revue d’histoire politique, 2011(n° 15). Online
BRUNET Pierre, Vouloir pour la Nation. Le concept de représentation dans la théorie de l’Etat, Paris, Publications de l’Université de Rouen, 2004.
Edit: formatting