What event is widely recognized as the official end of the Cold War?

The dissolution of the Soviet Union in December 1991 is widely recognized as the official end of the Cold War. This event marked the definitive collapse of the Soviet state, which had been the primary rival to the United States and its allies during the Cold War era. The end of the Soviet Union meant that the ideological and geopolitical confrontations characteristic of the Cold War essentially ceased, leading to the emergence of new independent states that were formerly part of the Soviet republics.

Moreover, this dissolution symbolized a permanent shift in global power dynamics and resulted in the reduction of nuclear arsenals, significantly altering international relations. While the fall of the Berlin Wall in 1989 was a significant moment that symbolized the weakening of Soviet influence in Eastern Europe, it was the ultimate disintegration of the Soviet Union that brought about the formal conclusion of the Cold War. Other options, such as the signing of the Treaty of Versailles, pertain to different historical contexts, and the establishment of NATO was part of the early Cold War strategy to counter Soviet expansion rather than an endpoint of the period.