Pugachev's Rebellion
Pugachev's Rebellion (Peasants' War 1773-75, Cossack Rebellion) of 1773-75 was the principal revolt in a series of popular rebellions that took place in the Russian Empire after Catherine II seized power in 1762. It began as an organized insurrection of Yaik Cossacks headed by Yemelyan Pugachev, a disaffected ex-lieutenant of the Imperial Russian Army, against a background of profound peasant unrest and war with the Ottoman Empire. After initial success, Pugachev assumed leadership of an alternative government in the name of the assassinated Tsar Peter III and proclaimed an end to serfdom. This organized leadership presented a challenge to the imperial administration of Catherine II.
Russian Enlightenment
Catherine greatly exaggerated Russia's economic stability and greatly misinformed Voltaire on the subject. For instance, Catherine in the correspondence never mentioned the Pugachev rebellion of 1773–74. When Voltaire brought up the subject, Catherine brushed it off by simply saying that she had it under control. As a result, Voltaire never realized the significant economic hardship of Russia's peasant class that had triggered the revolt.