So I'm far from an expert, but after thinking about it, and looking it over on wikipedia, it seems that every country that had its own internal, organic communist revolution was basically an agrarian society with an overwhelming peasant or poor farmer class, and then a small, wealthy ruling class.
Marx predicted that factory workers would organize in factories to wrest ownership and control of the means of production from the owners, but that doesn't seem to be what played out. One of the first major projects of the Soviet Union was to industrialize the country -- meaning it wasn't an industrial country beforehand. Broadly, the same seems to hold for China, Mongolia, Cuba, etc.
Some of the smaller countries got support from the Soviet Union and other communist states during their revolution, but that doesn't seem to change the basic motivation of a poor farmer class rising up against a landed class, which doesn't precisely align with what Marx predicted. Some countries were occupied by the Soviet Union after WWII, but that's not what I'm referring to. I'm looking at the ones that had their own revolution that overthrew their own governments.
Communists and Marxists seem especially interested in political theory. Have any of them ever noticed this pattern, and how it diverges from Marxist "orthodoxy"?
I can provide an answer to this question as it concerns the Soviet Union. Generally 19th century Marxist thought as postulated by figures like Vladimir Lenin did not believe that Russia would be the birthplace of the revolution that it was destined to become. Primarily, this was because of the reasons that you outline in your question: 19th century Russia was in many ways still quite feudal in its governance; though remember, serfdom had been ended in 1861 by Emperor Alexandr II, which allowed the peasant class some level of basic agency and autonomy.
The primary problem which these political thinkers were considering was called The Market Question, which was defined by Vladimir Lenin as follows in his essay On the Market Question (1893):
"Can capitalism develop in Russia and reach full development when the masses of the people are poor and are becoming still poorer?"
Essentially the heart of the question wonders exactly what you're wondering because capitalism is a required step in Marx's inevitable march to utopia.
On the Market Question is really quite a dry essay which sees Lenin mathematically postulating that capitalism is an inherently exploitive system whereby the capitalist classes consume surplus capital created by the working classes instead of reinvesting that wealth for the benefit of those whom Lenin argues created it. He calls this latter process of reinvestment "Accumulation," and in his socialist society, that Accumulation benefits the working class. Essentially, he is trying to argue that a capitalist society will inherently become socialized by the repetition of the former, exploitive process ad absurdum, where a growing class consciousness leads to revolution. This is pretty standard Marxist thought, and Lenin eventually hypothesizes that class consciousness must be more or less implanted in the head of the working classes by a Revolutionary Vanguard of Marxist leaders of the Revolution. This is the beginning of the creation of the body of thought known as Marxism-Leninism.
Lenin answers The Market Question in a much more reader-friendly way in The New Factory Law (1897), the following excerpt is going to be quite a long one so I apologize in advance, but I think it provides a really good overview of how Lenin's ideas about revolution in Russia were changing and how he began to believe himself that socialist revolution was possible there:
"The significance of the new factory law lies, on the one hand, in its being a forced concession by the government, in its having been won from the police government by the united and class-conscious workers. The promulgation of this law shows the success of the working-class movement in Russia; it shows what tremendous power lies in the class conscious and staunch demand of the working masses. No amount of persecution, no wholesale arrests and deportations, no grandiose political trials, no hounding of the workers have been of any avail. The government set all its forces and resources into motion. It hurled itself upon the St. Petersburg workers with all the weight of the tremendous power it commands. It hounded and persecuted the workers without trial and with unparalleled ferocity in the endeavour at all costs to knock the spirit of protest, of struggle, out of the workers, to crush the workers’ incipient socialist movement against the employers and the government. It was all to no avail, and the government was compelled to realise that no amount of persecution of individual workers would eradicate the workers’ movement and that it would have to make concessions. This autocratic government, considered to be all-powerful and independent of the people, had to yield to the demands of several tens of thousands of St. Petersburg workers. We have seen how insignificant and ambiguous these concessions are. But this is only the first step. The working-class movement has long ago spread beyond St. Petersburg; it is growing and expanding, embracing the masses of industrial workers with growing thoroughness all over the country. And when all these masses, led by one party, the socialist party, present their joint demands, the government will no longer be able to get away with such an insignificant concession!" (italics in the original)
Just for some context, the new law he refers to here has to do with improved worker conditions and was begrudgingly passed by Emperor Nikolai II in the face of worker strikes.
As you can see here though, as far back as 1897 Lenin is already framing the nascent worker's movement as an inherently socialist one. I don't think that's accurate, these people were not striking for revolution-- they were striking for basic worker's rights. The Emperor was the head of the Russian Orthodox Church and considered almost a god on earth; calling for his removal was a literal heresy to most people. There is an important process in the church-- anointing the head with oil during the equivalent of Orthodox baptism called krishenyie (крещение); normal people are anointed once in their lifetime, the emperor is anointed twice-- once at birth, and once at coronation. This shows how highly regarded this figure was. 1897 was several years before many of the blunders which really did result in the masses demanding the abdication of the emperor (things like Bloody Sunday, the Second Russo-Japanese War, Stolypin's assassination, etc.), though again, not the abolition of the monarchy which occurred.
Another thing to keep in mind is that the October Revolution was led by the workers in the imperial capital of Saint-Petersburg and then spread to the rural countryside. Most of the rural countryside was socialized by force. These were mostly peasants who did not support the Bolsheviks-- don't take that to mean they had no rural support, they did, but it was hardly the majority. So considering that fact, Marx was more or less right that the revolution would occur in the most capitalist part of the country, and really, the lack of government organization in the rural countryside made seizing power there a lot more simple for the Bolsheviks when the time came to do so.
Think of it like this, the revolution started in the factories and ended in the fields. Thus Marxist thought is technically correct here, even if only technically.
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