Question: The Molotov–Ribbentrop Pact was signed by the Foreign Minister of Germany who held the post during what years?
Sentence (from "Molotov–Ribbentrop Pact"): The Molotov–Ribbentrop Pact, also known as the Nazi–Soviet Pact, the German–Soviet Non-aggression Pact or the Nazi German-Soviet Pact of Aggression (officially: "Treaty of Non-aggression between Germany and the Union of Soviet Socialist Republics"), was a neutrality pact between Nazi Germany and the Soviet Union signed in Moscow on 23 August 1939 by foreign ministers Joachim von Ribbentrop and Vyacheslav Molotov, respectively.
Relevant evidence: Yes