However, after the victory of the Bolsheviks, the Left SRs accepted the
October Revolution, and Kamkov participated in negotiations with the Bolsheviks to form a coalition government. Kamkov favoured some agreements between all socialist parties, a popular position at the time, feeling that "the Left should not isolate itself from the moderate democratic forces." However, efforts to bring about such an all-socialist coalition quickly foundered on the opposition of both Lenin and the SR/Menshevik leaders. The Left SRs were the only party to enter a coalition with the Bolsheviks. Along with Isaac Steinberg,
A.L. Kollegaev,
Vladimir Karelin, V.Y. Trutovsky, V.A. Algasov and
P.P. Proshyan, Kamkov became a member of the
Council of People's Commissars (without portfolio). He was also elected to the new
Central Executive Committee of the All-Russian Congress of Soviets. The Bolshevik/Left SR coalition was short-lived. Although Kamkov supported the Left SRs' participation in the Russian delegation in the peace negotiations with Imperial Germany at
Brest-Litovsk, he was appalled by the harsh conditions imposed on Russia by the
Treaty of Brest-Litovsk, fearing that it would suffocate the Russian Revolution. Along with some 'Left Communists', the Left SRs called for rejecting the Treaty. The 'Left Communists' were eventually brought to heel, but in March 1918, the Left SRs resigned from the Soviet government in protest against the peace treaty. Soon afterward, following the so-called '
Left SR uprising', they were expelled from the soviets (the other socialist parties had already been expelled earlier, over the protests of the Left SRs). Kamkov was involved in many of the activities of the Left SRs over the next few months: organising resistance to the Brest-Litovsk Treaty and to the Bolshevik policy of forced grain requisitions, holding merger talks with the '
Socialist Maximalists' and Ukrainian revolutionary groups. ==Conflict with the Bolsheviks==