So, what was the reality? How much influence did the Soviet Union really have over Western peace movements?

I’m afraid no one here will be able to give you a definitive answer to this. It’s a highly contentious question for two reasons:

(a) One of the main pitfalls of contemporary history (i.e. the history of living memory) in general is that many historians of the period are also eye witnesses or even participants of the events and processes they describe. Scholars who were active in peace groups themselves have repeatedly denied any Soviet influence on the movement because they weren’t influenced themselves (and in turn saw any such suggestion as a personal attack). This has made scholarly debate on the issue difficult, and many historians won’t touch it with a barge pole.

(b) Unsurprisingly with such a controversial issue, much source material is either lost or classified. For example the Rosenholz files (documents of the GDR’s foreign intelligence agency seized in 1990, including information on its spy network) are officially open to the public but de facto kept under incredibly tight wraps and not generally accessible for researchers. Until this changes significantly, it is impossible to say how many Stasi agents were active in the West German peace movement, for example.

We do know that the 1969 International Meeting of Communist and Workers Parties passed a strategy of cooperation between communist parties and ‘anti-imperialist forces’ particularly in the West. However this didn’t really gain any traction until NATO voted to deploy American middle-range missiles in 1979 in an attempt to force the Warsaw Pact to negotiate disarmament measures. (NATO Double-Track Decision) This sparked a large wave of protest against NATO in Western Europe, giving the USSR the vehicle it had been preparing and hoping for.

The USSR undoubtedly did put large efforts into infiltrating the Western European peace movements as a strategy of weakening NATO. This largely failed in Italy and France, where Communists did not actively support anti-NATO protests through organization and funding, but was more successful in West Germany and the Netherlands.

For example the head of the Stasi’s foreign intelligence division stated in his memoirs that the Stasi had held signifcant control over one of West Germany’s most prominent peace organizations (Generale für den Frieden, i.e. ‘generals for peace’) and funded it with 100.000 DM per year. Researchers also found documents in the party archive of East Germany’s governing party (SED) proving that the GDR had supported another organization (Deutsche Friedensorganisation, i.e. ‘German peace organization’) with 5m DM annually. There is also evidence that the Stasi at least planned to plant agents at the 1982 party conference of West Germany’s Social Democratic Party (then the governing party) to move resolutions against NATO rearmament. (Which and how many of the conference delegates were Stasi spies, however, is one of the questions that can only be answered by the Rosenholz files.)

Many smaller peace groups in West Germany at the time also worked closely with the German Communist Party (DKP). Their meetings also mostly involved small numbers of activists and had a tendency to last for hours and hours, making it easy for Soviet/Stasi agents to exert disproportionately large influence on their decisions. (Simply because they were the guys who always showed up and stayed until the end.) This mainly meant discouraging such groups from criticizing Soviet armament policies and reaching out to peace groups in Eastern Europe, thus keeping their focus firmly on influencing public opinion in the West. In this respect, the Soviet Union never controlled Western protest groups outright, but it did have the capacity to significantly influence their decisions at times. These smaller groups however were soon supplanted by the newly formed Green Party (Die Grünen), which united much of the peace movement in a single organization and which the USSR tried by ultimately failed to infiltrate successfully.