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Campaigns targeting nationalities

A series of mass operations of the NKVD was carried out from 1937 through 1938 targeting specific nationalities within the Soviet Union, on the order of Nikolai Yezhov.

The Polish Operation of the NKVD was the largest of this kind. The Polish operation claimed the largest number of the NKVD victims: 143,810 arrests and 111,091 executions according to records. Snyder estimates that at least eighty-five thousand of them were ethnic Poles. The remainder were 'suspected' of being Polish, without further inquiry.

Poles comprised 12.5% of those who were killed during the Great Terror, while comprising only 0.4% of the population. Overall, national minorities targeted in these campaigns composed 36% of the victims of the Great Purge, despite being only 1.6% of the Soviet Union's population. 74% of ethnic minorities arrested during the Great Purge were executed while those sentenced during the Kulak Operation had only a 50% chance of being executed, (though this may have been due to the Gulag camp's lack of space in the late stages of the Purge rather than deliberate discrimination in sentencing).

The wives and children of those arrested and executed were dealt with by the NKVD Order No. 00486. The women were sentenced to forced labour for 5 or 10 years. Their minor children were put in orphanages. All possessions were confiscated. Extended families were purposely left with nothing to live on, which usually sealed their fate as well, affecting up to 200,000–250,000 people of Polish background depending on the size of their families. National operations of the NKVD were conducted on a quota system using album procedure. The officials were mandated to arrest and execute a specific number of so-called "counter-revolutionaries", compiled by administration using various statistics but also telephone books with names sounding non-Russian.

The Polish Operation of the NKVD served as a model for a series of similar NKVD secret decrees targeting a number of the Soviet Union's diaspora nationalities: the Finnish, Latvian, Estonian, Bulgarian, Afghan, Iranian, Greek, and Chinese. Of the operations against national minorities, it was the largest one, second only to the "Kulak Operation" in terms of the number of victims. According to Timothy Snyder, ethnic Poles constituted the largest group of victims in the Great Terror, comprising less than 0.5% of the country's population but comprising 12.5% of those executed.

Timothy Snyder attributes 300,000 deaths during the Great Purge to "national terror" including ethnic minorities and Ukrainian "kulaks" who had survived dekulakization and the Holodomor famine that had been used to kill millions in the early 1930s. Lev Kopelev wrote "In Ukraine 1937 began in 1933", referring to the earlier Soviet political repressions in Ukraine. There was also deadly persecution of Ukrainian cultural elites, who are referred to as the Executed Renaissance. Statistics of Ukraine's Ministry of Foreign Affairs indicate that about 200,000 victims of the Great Purge were Ukrainians.

Concerning diaspora minorities, the vast majority of whom were Soviet citizens and whose ancestors had resided for decades and sometimes centuries in the Soviet Union and Russian Empire, "this designation absolutized their cross-border ethnicities as the only salient aspect of their identity, sufficient proof of their disloyalty and sufficient justification for their arrest and execution" (Martin, 2001: 338). Some scholars have called the national operations of the NKVD genocidal. Norman Naimark called Stalin's policy towards Poles in the 1930s "genocidal". However, he does not consider the Great Purge entirely genocidal because it also targeted political opponents.

Some scholars, however, focus on the security dilemma in the border areas suggesting the need to secure the ethnic integrity of Soviet space vis-à-vis neighboring capitalistic enemy states. They stress the role of international relations and believe that representatives of these minorities were killed not because of their ethnicity, but because of their possible relations to countries hostile to the USSR and fear of disloyalty in the case of an invasion. Nevertheless, little proof exists to suggest that Russia's and Stalin's alleged prejudices played a central causal role in the Great Purge.