[3] In 1940, following the Molotov–Ribbentrop Pact and the Soviet ultimatum on 26 June 1940, Northern Bukovina (including the north and northwestern parts of the Rădăuți County) was occupied by the Soviet Union and incorporated into the USSR (Chernivtsi Oblast, Ukrainian SSR).

Rădăuți County (with its reduced territory) was re-established in September 1940 (after the fall of Carol II's regime) and completely re-instated (as part of the Bukovina Governorate) after Northern Bukovina was recovered by Romania in July 1941, following the invasion of the Soviet Union.

Nevertheless, in August 1944 the Northern Bukovina was taken over again by the Soviet Army and the borders as of 1 January 1941 were confirmed by the 1947 Paris Peace Treaties.

[1] Administratively, Rădăuți County was divided into three districts (plăși):[1] According to the Romanian census of 1930 the population of Rădăuți County was 160,778, of which 55.4% were ethnic Romanians, 11.1% Germans, 8.7% Ukrainians, 7.6% Hutsuls, 7.2% Jews, 6.4% Hungarians, 1.4% Poles, as well as other minorities.

[5] In 1930 the urban population of Rădăuți County was 26,693 (the city of Rădăuţi had 16,788 inhabitants, and Siret had 9,905), which included 38.3% Romanians, 28.9% Jews, 23.5% Germans, 4.7% Ukrainians, 1.8% of Poles, as well as other minorities, by ethnicity.