Answer: Vyacheslav Molotov. In 1939, Molotov became the Soviet foreign minister, and it was for his signature on the Nazi-Soviet non-aggression pact—the Molotov-Ribbentrop Pact—that he became best known.
Explanation: When Joseph Stalin returned to the capital, he reversed Molotov's line, but when Lenin arrived, he overruled Stalin. However, Molotov became a protégé of and a close adherent to Stalin, an alliance to which he owed his later prominence.