A week later, the Germans invaded Poland on two fronts; on Sept. 17, the dismemberment process continued when the Soviets marched into Poland from the east.
The secret protocol also divided Romania, Lithuania, Latvia, Estonia and Finland into respective German and Soviet “spheres of influence,” anticipating “territorial and political rearrangements,” most of which subsequently took place.
Adolf Hitler’s foreign minister, Joachim von Ribbentrop, had flown to Moscow to sign the pact with his Soviet counterpart, V.M. Molotov, as a smiling Joseph Stalin looked on approvingly. The accord came as a shock in Britain and France; their envoys were in Moscow only days before trying to forge a broad mutual alliance with the Kremlin.
Starting in mid-March 1939, in an attempt to contain Hitler’s expansionist goals, the Soviet Union, Britain and France traded plans regarding a potential political and military agreement. Although informal consultations had begun in April, negotiations did not start in earnest until May. At the same time, throughout early 1939, Germany had secretly hinted to Soviet diplomats that it could offer better terms for a political agreement than could the Western allies.
After the deal was signed, the Soviet Communist hierarchy sought to minimize its prior opposition to the Nazis during the Spanish Civil War and elsewhere. Molotov reassured the Germans of his good intentions by telling journalists that “fascism is a matter of taste.” For its part, Nazi Germany also did an about-face over its prior virulent opposition to the Soviet Union, although Hitler privately continued to view an attack on the Soviet Union as "inevitable.”
On June 22, 1941, the Germans invaded the Soviet Union. Within six months, German tank officers could see the Kremlin’s spires through their binoculars. The Red Army had suffered 4.3 million casualties while Germany had captured 3 million Soviet prisoners, most of whom did not survive the war.
Stalin had ignored several warnings that Germany would break the pact and was likely to invade. The Soviets continued to export raw materials to Germany until the outbreak of hostilities. These exports enabled Germany to maintain its stocks of rubber and grain from the first day of the invasion until October 1941.
Successive Soviet leaders denied the existence of the secret protocol until 1989, when it was acknowledged and denounced. More recently, Russian revisionist historians have defended the pact as a necessary geopolitical measure at the time. These views have been endorsed by Russian President Vladimir Putin and Sergei Lavrov, the Russian foreign minister.