Short Answer 
The Great Purge, initiated by Stalin in the late 1930s, aimed to eliminate perceived threats to his power following the assassination of Sergey Kirov in 1934. This campaign led to millions being arrested or killed, instilling widespread fear and paranoia while significantly weakening the Communist Party and military structures in the Soviet Union.
Step 1: Understanding the Great Purge
The Great Purge was a significant political campaign initiated by Joseph Stalin during the late 1930s. This period was characterized by the systematic elimination of perceived threats to Stalin’s leadership. The campaign primarily targeted members of the Communist Party, military leaders, and ordinary citizens who were seen as a challenge to Stalin’s power.
Step 2: The Trigger Event
The assassination of Sergey Kirov in December 1934 served as a crucial catalyst for the Great Purge. Many believe that Stalin orchestrated Kirov’s murder to justify a widespread crackdown on political opponents. This event marked the beginning of an era where millions were arrested, executed, or sent to labor camps under the guise of protecting the state.
Step 3: Impacts of the Great Purge
The Great Purge resulted in the deaths and imprisonment of millions, leading to a climate of fear and paranoia throughout the Soviet Union. The repercussions of this campaign were profound, as it not only decimated the Communist Party’s ranks but also weakened the military’s structure. Some key impacts included:
- The execution of many high-ranking officials and military leaders.
- The establishment of a culture of suspicion among citizens.
- Long-term effects on Soviet society and governance.