I was wondering this while reading about Allende's presidency in Chile, and the involvement of the US government and its agencies in destabilising the Chilean government, funding strikes and how, as Kissenger put it, "they created the conditions as great as possible" for Pinochet's coup. This seems to have been motivated purely by ideology rather than the merits of Allende's policies.
Other examples of leftist or anti-imperialist governments (or those who at least took concrete steps to reduce the involvement of foreign interests in their economies) being usurped by western powers include in Burkina Faso under Sankara (disputed, but the involvement at least of the French seems something of an open secret), Uruguay, Argentina, Bolivia, Brazil and other South American nations, Iran, and of course the Bay of Pigs and the Vietnam war to name just a few.
I know that the coup which brought Sankara himself to power may have had involvement from Ghaddafi's Libya, and of course Che Guevarra was killed while attempting to foment revolution in Bolivia - but I am curious about the extent to which the USSR attempted to fund regime change across the world.
How much time and resources did they invest in this sort of scramble for ideological allies? Of course there was the Warsaw pact, but this was not on the scale of Operation Condor's influence of an entire continent, and due to the geographical proximity such influence would surely come cheaper, on top of the opportunity presented by being able to pick and choose the new government post-WW2 after the Red Army pushed from Moscow to Berlin. Perhaps the governments I mention as being overthrown by the west had received backing from the USSR in the first place?
Any insight would be most welcome, apologies if this question is poorly worded!
The short answer is that they did, so I'll give a few examples from Africa. I'm not going to go to too much detail on each of these as the question is very wide in scope, and I don't have an expert insight on any of these conflicts, so I will do the drudge work of listing brief mentions in case an expert comes along and wants to elaborate on any of them.
The first one that comes to mind is the Soviet assistance extended toward the MPLA of Angola. MPLA was an ostensibly Socialist faction, but really one that was more interested in securing independence. Formed a few years before a long war of independence, MPLA fought in the war, which Portugal actually won militarily. However, the Carnation Revolution happened, and with it, Angola got its independence.
Once Angola no longer had a colonial overlord, the Angolan factions, having fulfilled the wish for independence which was the only thing they had in common in comparison to the surfeit of differences they had, did something very predictable and turned on one another. In the ensuing Civil War, which lasted on and off until 2002 (!), the Soviet Union provided assistance to MPLA, in the forms of arms, equipment, and even deployed troops. Romania from the Warsaw Pact also pitched in, and was mostly helping by providing training. MPLA renounced ties to Socialism in favor of a western alignment in 1990, and the Soviet Union did not live to see the conclusive victory, but it can be said that Soviets were quite proactive in ensuring MPLA won.
Another case is that following the revolution of 1974, Ethiopia became a Marxist state, and the Soviet Union supported them for a short while against Eritrea in the Eritrean War of Independence. They also supported them during the revolution, and also during the war that the new Marxist Ethiopia inherited from the previous empire, a war which had been going on for over a decade.
The Egyptian Revolution of 1952, was funnily enough, supported by both the US and the Soviet Union, and Nasser maintained good relations with the Soviets until his death. After his death, relations soured.
Those are the "success" stories, as in the very generous definition of providing considerable support and actually getting a Socialist state that lasted at least a few years. Beyond that, there were failures to get results from varying degrees of effort in Morocco, Congo, and Algeria.
In general, African conflicts were more anti-Colonial than Socialist in nature, and a lot of the "successes" turned away from Socialism if they ever were Socialist, in short order. It was a good time to be an African rebel, you could declare that you were a Socialist and get world class support and funding, but my personal opinion is that few of these attempts at Socialism were in earnest.