The Cold War is commonly understood to have ended in 1991. This period of geopolitical tension primarily involved the United States and its NATO allies on one side, and the Soviet Union and its allies on the other. The fall of the Berlin Wall in 1989 is often seen as a pivotal moment symbolizing the decline of Soviet influence in Eastern Europe. The formal conclusion of the Cold War is marked by the dissolution of the Soviet Union in December 1991, leading to the emergence of independent republics and a new world order.