Mass operations of the People's Comissariate of Internal Affairs (NKVD)^[1] were carried out during the Great Purge and targeted specific categories of people. As a rule, they were carried out according to the corresponding order of the People's Commissar of Internal Affairs Nikolai Yezhov.

The operations of this type in this period targeted "foreign" ethnicities (ethnicities with cross-border ties to foreign nation-states), unlike nationally targeted repressions during World War II. According to historian Oleg Khlevniuk, Stalin became concerned about rearguard uprisings that were seen in the Spanish Civil War and believed that "nationalities of foreign governments" posed a threat in border regions, even if they were Soviet citizens whose ancestors had sometimes lived decades or centuries in the areas controlled by the Soviet Union.^[2]

Minutes of the January 31, 1938 Politburo meeting list the following ethnicities against which NKND operations were to be continued: Poles, Latvians, Germans, Estonians, Finns, Greeks, Iranians, Harbinites, Chinese, and Romanians. It was also suggested to carry out similar NKVD operations against Bulgarians and Macedonians. ^[3]

From August 1937 to October 1938, 353,513 people were arrested and 247,157 were shot in the national operations of NKVD. It is estimated that this would make up 34% of the total victims of the Great Purge.^[4]

• Polish Operation of the NKVD ~111,091 killed^[5]
  • NKVD Order No. 00485
• German Operation of the NKVD ~41,898 killed^[6]
• Greek Operation of the NKVD ~20,000^[7]—50,000^[8]
• Latvian Operation of the NKVD 16,573 killed^[9]
• Korean Operation of the NKVD ~40,000 killed^[10]
• Chinese Operation of the NKVD
• Estonian Operation of the NKVD 4,672 killed^[11]
• Finnish Operation of the NKVD 8,000–25,000 killed or disappeared^[12]
• Harbin Operation of the NKVD ~30,992 Harbin Russians were killed^[13]

• NKVD Order No. 00447, an operation to repress ex-kulaks, criminals, and other anti-Soviet "elements"^[14][15]
• Family members of traitors to the Motherland

On November 17, 1938 a joint decree No. 81 of Sovnarkom USSR and Central Committee of Communist Party of the Soviet Union Decree about Arrests, Prosecutor Supervision and Course of Investigation and the subsequent order of the NKVD undersigned by Lavrentiy Beria cancelled most of NKVD orders of mass type (but not all, see, e.g., NKVD Order No. 00689) and suspended implementation of death sentences, signifying the end of the Great Purge ("Yezhovshchina").

• Soviet deportations from Bessarabia and Northern Bukovina (1940-1951)
• Genocide of the Ingrian Finns
• Mass killings under communist regimes