The French went from a monarchy, to a brief dictatorship, to an Empire, and to my understanding the French would proclaim 4 republics over the course of history to the present. If the Republic was so short-lived why do we consider the first French revolution to be significant?
Your question presumes the idea of 'progress' - that history is a linear development slowly building up to the world we have today, and past events should be remembered primarily in terms of how they led us here. This view is far from uncommon, but historians need to be very careful not to project modern values and assumptions backwards onto the past. The French Revolution was immensely significant at the time because it changed Europe socially, politically, militarily and ideologically. Many of those changes are still with us, others have faded away or been overtaken by subsequent changes.
Politically, socially and ideologically, the French Revolution is often credited as the birth of the modern nation-state. It began a process whereby the inhabitants of France actually became French, giving people a sense of national identity and standardising language, culture and administration. It changed people's political identity by both expanding it horizontally (no longer just Norman or Parisian, now French) but also vertically (not just a peasant, now a citizen). In doing so, it swept away the last cobwebs of the middle ages. By then exporting the revolution intellectually (Jacobinism) and militarily (Napoleon) this process was echoed across the continent. For example, the Holy Roman Empire was finally dissolved.
Militarily, the creation of a nation meant the possibility of a national army. With the levee en masse (conscription) Napoleonic France completely changed how war was fought. Gone was the gentlemanly manouvre of small professional armies. Instead, huge armies of enthusiastic patriots able to break free from supply lines and 'live off the land', only to come together and overwhelm the enemy in massed column melee attacks. As Napoleon put it: "You cannot stop me; I spend 30,000 lives a month." Even bulwarks of monarchical conservatism such as Prussia were forced to respond by imitating the French militarily, but conscription isn't something the army can just do - ultimately, the state of Prussia had to make significant domestic political and social concessions as a result.
In summary, the French Revolution created the nation-state of France. Then, it gave Napoleon the tools to export that Revolution. By a combination of direct imposition and indirect imitation, this had a significant impact on countries across Europe.
I'm sorry my english is actually pretty weak.
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The idea of a creation from scratch of nation-state of France is actually forsaken by academic history.
Today, the historical consensus is about a progressive construction of french nation-state since roughly the 10th century.
It's wrong to say that, overnight, one inhabitant of France would wake up considering himself french, and the idea of a creation of the nation state of France only with the Revolution was largely diffused during the 19th and 20th century, exactly because the republican party had to legitimize himself in a century where everything was to built and France was seeking his equilibrium.
During the Ancien Régime, the idea of nation was not evocated because we must understand that the concept of nation was not even created. And that is where the problem is : in fact, we see that what we today call as nation would, indeed, be seen in some ways (and more and more) during the Ancien Régime.
I will quote Alain Talon, a reference in History, who is criticizing the supporters of a creation of nation-state during the Revolution :
« Voilà le défaut de tenir la définition de la nation comme un concept intemporel alors que le contenu qu’ils donnent à ce concept est lui bien lié à une époque bien précise : le XIXe siècle »
"Here is the fault of seeing the definition of nation as a timeless concept wereas the meaning they give to this concept is linked to a specific era : the 19th century."
My translation should be horrible, but what he tries to say is that people who considered nation as a Revolutionnary creation, used the values of the 19th century to seek for similarities in the past, which they obviously could not find.
I will quote Anne Marie Thiesse in La Création des identités nationales, Europe, XVIIIe – XXe siècle, which she is a fervent defensor of the idea that nation was invented at 100% during Revolution.
"La véritable naissance d'une nation, c'est le moment où une poignée d'individus déclare qu'elle existe et entreprend de le prouver. Les premiers exemples ne sont pas antérieurs au XVIIIe siècle : pas de nation au sens moderne, c’est-à-dire politique, avant cette date. [...] À l'aube du XIXe siècle, les nations n'ont pas encore d'histoire. [...] L'idée de nation est née du combat contre le pouvoir monarchique et la division sociale en ordres aux droits inégaux."
My translation:
"The true born of a nation, is where a group of individuals declares that it exist, and undertakes to prove it. The first exemples are not before 18th century : no nation at a political meaning before this date. [...] Before 19th century, nations still don't have an history. [...] The idea of nation is born from the battle against monarhcy et against social division in orders and inequals rights."
During the Ancien Régime, monarchs but also peasants constructed ideals, true or non-true figures that would incarnate the kingdom, a part of the kingdom, or a value to fight for.
Joan of Arc is a good exemple. Charles VIIth, after winning the hundred years war, reviewed the trial of Joan of Arc and sanctified her in order to cement the kingdom. Even if the actual military utility of Joan of Arc is largely question to debate, she was actually a way to unite the king's subject, which is what we consider today as a part of the definition of the nation.
I'll quote the pope who sanctified Joan of Arc :
« C'est que, par son conseil, les habitants de Reims sont revenus à l'obéissance [...] Par sa pénétration et son habileté les affaires des Français ont été solidement reconstituées. »
"By her advices, Reims' unhabitant came back to obedience. [...] By her penetration et her hability, the french's affairs were firmly reconstituted"
Another hero like that who is not known is Le Grand Ferré who has the particularity of being a hero of the peasants. The recent works of the historian Colette Beaune showed that Le Grand Ferré was indeed, at that time, a very popular man and was constructing a collective identity and imaginary to the subject of french kingdom.
During the war of Spain succession, the kingdom of Louis XIV was in such trouble that the king had to write down a message which was read in every villages : an excerpt. (1709)
"Je suis persuadé qu’ils s’opposeraient eux-mêmes à la recevoir à des conditions également contraires à la justice et à l’honneur du nom FRANCAIS."
"I'm persuated that they would themselves be opposed to received condition [peace conditions], that are opposed to the justice and the honor behind the word of FRENCH"
I quote Fernand Braudel : Identité de la France
[La nation est] un résidu, un amalgame, des additions, des mélanges. S'il s'interrompait, tout s'écroulerait. Une nation ne peut être qu'au prix de se chercher elle-même sans fin, de se transformer dans le sens de son évolution logique.
[Nation is] a residue, an amalgam, additions, mixings. If it would stop, everything would crush down. A nation is at the only price to find herself without any ending, to transform herself in the way of her logical evolution.
What is certain is that Revolution have created a new society where the idea of nation was the main pillar, and yes, the Revolution actually was, maybe, the last stone of the nation-state construction of France.
I will quote Anatole Prevost Paradole in La France Nouvelle :
The French Revolution had found a new society, she would yet seek for her gouvernment
Before Revolution, the word of "Nation" would designate a minority community living in another majority comunity. After the Revolution, nation was indeed what was caracterizing France.
To understand that, I like the preface of the book : 1789 - 1815, Revolution Consulate, Empire, which talk about the idea of nation and Revolution. Unfortunately, I cant translate it entirely.
In fact, what invented Revolution was the notion of sovereignety of nation : "La nation reprend toute sa souveraineté", Choudieu, 10th august 1792. ["Nation is taking back all of her sovereignety"].
Nation was being the motive of dying and living, that is what is incredible with Revolution.
During middle-age, dying for the homeland had striclty not a single oz of meaning. The only sacrifice you could do was for god : it's the crusade.
But I will quote Jean Tulard, specialist of Revolution :
"En criant "Vive la nation !" à Valmy, les soldats de Dumouriez avaient enterré l'Europe cosmopolite des Lumières et annoncé les mouvements de 1830 et 1848 [...] La féodalité disparaît ou recule de façon spectaculaire, les idées de liberté ou d'égalité font leur chemin sur le continent."
"By shouting "Long live the nation !" at Valmy, Dumouriez's solders had bury the cosmopolitan Europe of the Enlightenment et announced the movements of 1830 and 1848. [...] Feodality vanished or retreated in a spectacular way, the ideas of liberty and equality are making their way to the continent."