On December 1, 1934 Sergei Kirov, a close associate of Stalin, was assassinated . This prompted Stalin to institute another great purge. In the previous year, Stalin had purged the Communist Party of close to 1,000,000 members. This time, many of the older leaders of the party, such as Zinoviev and Kamenev, were arrested and tried for treason. Before the purges ended, close to 8 million people were killed, imprisoned or sent to Siberia.
During 1934 it seemed that the Soviet Union was normalizing, with the secret police being a little less invasive and rumors of a pardon for opponents of the regime widespread. Culturally Soviet youth began to adopt European methods of dress. The Soviet Union even joined the League of Nations.
All of this came to a sudden halt on December 1 when Sergei Kirov, a member of the Politburo who was responsible for heavy industry, was assassinated in Leningrad. Stalin immediately left for Leningrad. On arrival, he publicly slapped the waiting head of NKVD. The murder of Kirov was said to have been carried out by Leonid Nikolaev, and the government claimed that he was part of a Trotskyite-Zinovieite terror organization. Nikolaev was quickly shot, and almost everyone who was around suddenly died or disappeared. To this day, Kirov's assassination's actual circumstances are unclear, but many suspect that Stalin was behind it.
Stalin made use of the event to crack down on all forms of dissent. Before he left Moscow for Leningrad, he issued a decree that;
Arrests and executions became widespread. Of the 1,225 Communist delegates to the 17th Party Congress in 1934, 1108 were arrested within a year. Of the 139 candidate members to the Central Committee, 98 were arrested and shot.
The arrests and executions gathered more steam in 1935. Taking Stalins orders seriously, three people, two women, and a man, were arrested for asking questions about Kirov's death on March 9. They were executed on the 10th, and the next day the 11th, Stalin was notified. Tens of thousands of relatives of those accused were sent to work camps in the far east, known as the Gulags. Stalin even issued a decree that children as young as 12 should be executed for crimes against the state.
The Russian Orthodox Church became a new target of the assault by Stalin. Everywhere churches that were hundreds of years old were demolished.