I am reading Mazower's The Greek Revolution and he notes that while the Filiki Eteria were unusually influential they were not unique as a revolutionary secret society at the time. They were also a source of serious concern for conservatives like Metternich, and drove a great deal of despotic domestic policy.
Mazower briefly notes that they sprung up after the defeat of Napoleon but it isn't really the focus of the book, so I am curious for more detail on them. Likewise they seem to have been modeled on earlier examples like the Freemasons (which I suppose are only semi-secret) and the Illuminati.
First, what a coincidence! I'm also reading Mazower's The Greek Revolution at this moment.
I'll let other people go into more detail about the 18th Century origins of secret societies, as that's not my specialty. The short answer is that the Freemasons are the giant in the room, but far from the only secret society.
By the time you get to the 19th Century, the Freemasons are still around, along with tons of other societies across the social and political spectrums. As historian Robert Tombs wrote about 19th Century France (my particular specialty), French political culture at the time had "a paranoid obsession with conspiracies, a lurid world inhabited not only by cranks and simpletons, but by serious and influential thinkers and statesmen."
There were also good reasons for people to meet in secret societies, especially in continental Europe. Most countries in the early 19th Century censored newspapers, and many cracked down on pamphlets and books, too. Laws restricting public association were common. And many countries had so-called cabinets noir or "dark chambers" — government intelligence offices devoted to secretly reading people's letters. The police had wide networks of informants devoted to tracking not criminals but political dissidents. If the thing you wanted to talk about was at all subversive — and the bar for subversion could be pretty low in places like Austria, Prussia, or (to a lesser extent) Restoration France — it could make good sense to do it behind closed doors, cloaked by vows of secrecy.
While Freemasonry was, as I said, the most prominent secret society, it was far from the only one. In France a group of royalists formed the Chevaliers de la Foi or Knights of the Faith, an explicit Catholic imitation of Freemasonry. They worked to bring about the replacement of Napoleon by the Bourbons, and after that happened (mostly due to outside powers, but with a small but significant role by the Chevaliers) to coordinate political strategy. Masonic lodges could vary wildly, with some being little more than social clubs, and others backing much more radical political programs.
In the context of the 1820s, the other giant secret society we need to discuss is the Carbonari. Originally started in Italy to resist Napoleon, this group swiftly pivoted to oppose the reactionary governments imposed after Napoleon's downfall. They generally supported republics or constitutional monarchies, and were prepared to use force to achieve these ends. In 1820, Carbonari groups successfully launched a series of Italian revolutions, first in Sicily and Naples and then in northern Italy.
These Italian uprisings were happening a few months after a mutiny in Spain had forced King Ferdinand VII to accept a constitution — and after the heir to the French throne, the Duc de Berry, had been assassinated outside the Paris Opera. Then in 1821 the Etaireia launched a Greek rising in the Ottoman Empire.
Not all these events were launched by secret societies, but some were, and the net effect of all this uproar was to accentuate a sense of paranoia and conspiracy — and a powerful belief in the ubiquity and effectiveness of secret societies. This was most pronounced on the right wing, where it was commonly accepte that there was a secret, Paris-based comité directeur or steering committee, which was masterminding all these revolutions around Europe. People like Tsar Alexander, Metternich and British foreign minister Castlereagh talked about the comité directeur the same way a comic book character might discuss a league of supervillains like Hydra; it supposedly included a rogue's gallery of prominent revolutionary leaders like the Marquis de Lafayette.
Tsar Alexander, for example, became convinced that the comité directeur had caused a recent revolution in Greece — not for the sake of the Greeks, but to distract the Tsar from crushing the rebellion in Naples. “Be no doubt,” Alexander wrote, “that the impulse for this insurrectionary movement was given by that same comité central directeur of Paris, in the hope of making a diversion… and preventing us from destroying one of those synagogues of Satan, established solely in order to defend and propagate his anti-Christian doctrine.” (By all these theologically laden and antisemitic terms, just to be clear, Alexander meant liberalism.)
One of the few skeptics among the conservative powers-that-be was the French prime minister, the Duc de Richelieu, who scornfully wrote that "it is perhaps more convenient to attribute to an invisible power whose lever is in France… catastrophes whose real cause could more simply be found in the weakness and incompetence of those governments which a mere breath has been enough to overthrow."
Richelieu, as it happened, was mostly right. The comité directeur didn't exist (though some of its alleged members, like Lafayette, were absolutely up to their necks in less-sweeping conspiracies). But in a sense it didn't matter that much, because there absolutely were lots of very real secret societies plotting revolution. The success of the Italian Carbonari and the Spanish mutiny provoked a wave of imitators, including a French version of the Carbonari, the Charbonnerie.
Groups of French army officers attempted several different Spanish-style coups from 1820 onward (all unsuccessful, because the French regime was on much sturdier footing than the bumbling Ferdinands of Spain and Naples). The Charbonnerie launched a somewhat more coordinated series of attempted risings in late 1821 and early 1822; all these failed, too, though not before giving the powers that be a bit of a scare.
Years later, one of the French Carbonarists reflected back on these heady days, wondering, "Why did we have the mad idea that a government supported by laws and by the weight of inertia of 30 million men could be overturned by the plots of law students and second lieutenants?" Well, the idea didn't seem quite so mad in the immediate aftermath of the Italian and Spanish revolutions, nor in the context of widespread contemporay paranoia about the supposed efficacy and ruthlessness of the Freemasons (by the right) and the Jesuits (by the left).
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