Final answer:
Sergei Kirov's assassination was instrumental in Stalin's consolidation of power, precipitating the Great Purges. Nikolayev targeted Kirov possibly due to a personal grudge related to his wife's alleged affair with Kirov. This incident catalyzed Stalinist repressions and fundamentally transformed the political structure of the USSR.
Step-by-step explanation:
The assassination of Sergei Kirov on the 1st of December 1934 by Leonid Nikolayev was a significant event with far-reaching political implications in the Soviet Union. Kirov was a high-ranking Soviet politician, and his death was used by Stalin to launch a campaign against perceived enemies, leading to the Great Purges. The purges were a series of campaigns to eliminate dissent within the Communist Party and consolidate Stalin's authoritarian power.
Nikolayev was a disgruntled Communist Party member who harbored animosity towards Kirov, allegedly partly motivated by the belief that Kirov was involved romantically with his wife. This personal vendetta, mixed with the existing political disquiet, set the stage for what would become a pivotal moment in Soviet history. The assassination gave Stalin the pretext to initiate a period of intense political repression.
The alleged affair between Kirov and Nikolayev's wife might have contributed a personal motive to the assassination, but the broader significance of the event was its exploitation by Stalin to fuel his campaign of terror. The aftermath saw the elimination of many potential rivals and established Stalin's dictatorship, which led to the widespread suffering through Stalinist repressions and the alteration of the Soviet political landscape towards a totalitarian regime.