Kornilov had the support of the British military attaché, Brigadier-General Alfred Knox, and Kerensky accused Knox of producing pro-Kornilov propaganda. Kerensky also claimed Lord Milner wrote him a letter expressing support for Kornilov. A British armoured car squadron commanded by Oliver Locker-Lampson and dressed in Russian uniforms allegedly participated in the coup.
Over the course of the next few days, as the Provisional Government tried to come up with a concrete plan to avert the oncoming attack, the Petrograd Soviet had taken measures to defend against Kornilov‘s advancing troops. One of these measures was the creation of the Committee for Struggle Against Counterrevolution on 11 September 1917 (28 August Old Style). Those participating in the committee were representatives of the two national soviet executive committees of workers and soldiers and of peasants, the Petrograd Soviet, the General Central Council of Trade Unions, and the Social Revolutionary (S. R.) and Menshevik parties. The most notable members of this committee were the Bolsheviks, who had a large support base among the lower class, and included organizers such as Leon Trotsky, who had been previously imprisoned but released at the behest of the Petrograd Soviet to assist in the organization of the defense of Petrograd.
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The biggest beneficiary of the Kornilov affair was the Bolshevik Party, who enjoyed a revival in support and strength in the wake of the attempted coup. Kerensky released Bolsheviks who had been arrested during the July Days a few months earlier, when Vladimir Lenin was accused of being in the pay of the Germans and subsequently fled to Finland. Kerensky‘s plea to the Petrograd Soviet for support had resulted in the rearmament of the Bolshevik Military Organization and the release of Bolshevik political prisoners, including Leon Trotsky. Though these weapons were not needed to fight off Kornilov‘s advancing troops in August, they were kept by the Bolsheviks and used in their own successful armed October Revolution.