In the early 1900s,
Lavr Kornilov was a hero to the Russian people, and
Commander in Chief of the Russian army. Unlike most Russian generals, who were first and foremost politicians, Kornilov was a fighting man, and had no defence against
political trickery.
In 1917, shortly after the overthrow of the Tsar, Kerensky, leader of the Provisional Government, fearing General Kornilov's great support from the people, decided to paint him as a traitor. Kerensky ordered Kornilov to move troops into Petrograd for defence, yet claimed that Kornilov was attacking Petrograd as a rebellion, and had him arrested.
There are two great ironies in the supposed rebellion. Firstly, after Kornilov was arrested, Kerensky decided to temporarily reinstate Kornilov as leader of the armed forces for lack of a better general to take his place. Who in their right mind would put a man who they personally claimed to be a traitor trying to establish a dictatorship in charge of the military?! The second irony is the fact that though this entire ploy was designed to increase Kerensky's strenght, it actually gave the Communists the chance they needed to establish the Red Army -- supposedly to defend Petrograd.