Lenin’s seizure of power in October was rapidly followed in December by the Brest-Litovsk armistice, which put an end to the Russo-German war, which was a setback for the French diplomatic mission. Zinovy returned to Paris, but the French government, aware of the diplomatic capabilities of Captain Peshkov, soon sent him to advise the White Armies on all the fronts of the civil war which was then bloodying Russia. He was promoted temporary head of a battalion for the duration of his mission from December 9, 1918. He also met the ataman of the Cossacks, Semenov, in Vladivostok, then Admiral Kolchak in the Urals to help him in reorganizing his army. The defeat of the latter sent him in February 1920 to the Caucasus, where he attempted in vain to play a role with General Wrangel. The definitive victory of the Red Army over the Whites in November obligated Peshkov to return to Paris.