cold war timeline By 12695184 May 31, 1946 Korean War 1950-1953 Mar 12, 1947 US Uses Atomic Bombs End WWII. 1945 Jul 23, 1947 USSR Tests First Nuclear Weapon 1949. Jun 12, 1948 Berlin Blockade and Airlift. 1948-1949. Jul 22, 1957 The Space Race Begins 1957 Feb 14, 1960 USSR Tests the largest Nuclear Weapon 1960 Sep 21, 1975 Vietnam War 1959-1975 Sep 28, 1975 US Tests First Hydrogen Bomb 1950 May 23, 2023 timeline