Mezue ahịrịokwu na-esonụ: Na June 1940, Soviet Union ji ike weghara Estonia, Latvia, na Lithuania. O weghachikwaara mpaghara ndị Romania a na-ese okwu nke
Bessarabia, Northern Bukovina, na Hertza. Ma mgbe usuu ndị agha Germany wakporo Soviet Union n'Opereshọn Barbarossa na June 1941 ma kwupụta agha megide United States na December 1941, Soviet Union na mba ndị jikọrọ ya na ha rụkọrọ ọrụ ọnụ ịlụso Germany ọgụ. Briten bịanyere aka n'akwụkwọ nkwekọrịta ha na mba ndị ọzọ jikọrọ aka, Amerịka bịanyekwara aka n'akwụkwọ nkwekọrịta ha na mba ndị ọzọ jikọrọ aka. N'oge agha, United States nyere Britain, Soviet Union na mba ndị ọzọ so n'Òtù Ndị Agha ahụ ihe site n'usoro Lend-Lease ya. Otú ọ dị, Stalin nọgidere na-enwe obi abụọ, o chekwara na ndị Britain na ndị America gbakọrọ aka mee ka ọ bụrụ ndị Soviet ka agha ahụ a na-alụso Germany ga-aka njọ. Dị ka echiche a si dị, ndị Western Allies kpachaara anya na-egbu oge na-emeghe nke abụọ mgbochi German n'ihu iji tinye aka na nke ikpeazụ nkeji na-akpụzi udo mmezi. N'ihi ya, echiche ndị Soviet nwere banyere Ebe Ọdịda Anyanwụ Ụwa mere ka e nwee oké esemokwu na ibu iro n'etiti mba ndị ahụ jikọrọ aka.