He served in Russian army during the Seven-years' war of 1756-1763 against Prussia and during the 1768 - 1770 campaigns of the Russo-Turkish war of 1768 - 1774 rising to the Cossack rank of khorunzhiy (corresponds to the regular army rank of podporuchik or junior lieutenant in modern terminology).
In August of 1773 Pugachev organized the insurrection of the Yaik Cossacks which ignited the flames of the all-out peasant war in the lower Volga region. Pugachev pretended to be the "miraculously survived" Piotr Fiodorovich, former Emperor Peter III of Russia, who was deposed and killed in 1772.
After the first successes of Pugachev rebellion, the Cossack-peasant army was defeated by the government troops. Pugachev's comrades-in-arms betrayed him in September of 1774. Suvorov put the leader of the rebellion in the metal cage and sent him to Moscow to be publicly executed soon thereafter.