The Space Race began on August 2, 1955, when the Soviet Union responded to the US announcement four days earlier of intent to launch artificial satellites for the International Geophysical Year, by declaring they would also launch a satellite "in the near future". The Soviet Union beat the US to this, with the October 4, 1957, orbiting of Sputnik 1, and later beat the US to the first human in space, Yuri Gagarin, on April 12, 1961. The "race" peaked with the July 20, 1969, US landing of the first humans on the Moon with Apollo 11. The USSR tried but failed crewed lunar missions, and eventually canceled them and concentrated on Earth orbital space stations.
A period of détente followed with the April 1972 agreement on a co-operative Apollo–Soyuz Test Project, resulting in the July 1975 rendezvous in Earth orbit of a US astronaut crew with a Soviet cosmonaut crew. The end of the Space Race is harder to pinpoint than its beginning, but it was over by the December 1991 dissolution of the Soviet Union, after which true spaceflight cooperation between the US and Russia began.
The Space Race has left a legacy of Earth communications and weather satellites, and continuing human space presence on the International Space Station. It has also sparked increases in spending on education and research and development, which led to beneficial spin-off technologies.
The origins of the Space Race can be traced to Germany, beginning in the 1930s and continuing during World War II when Nazi Germany researched and built operational ballistic missiles capable of sub-orbital spaceflight. Starting in the early 1930s, during the last stages of the Weimar Republic, German aerospace engineers experimented with liquid-fueled rockets, with the goal that one day they would be capable of reaching high altitudes and traversing long distances. The head of the German Army's Ballistics and Munitions Branch, Lieutenant Colonel Karl Emil Becker, gathered a small team of engineers that included Walter Dornberger and Leo Zanssen, to figure out how to use rockets as long-range artillery in order to get around the Treaty of Versailles' ban on research and development of long-range cannons. Wernher von Braun, a young engineering prodigy, was recruited by Becker and Dornberger to join their secret army program at Kummersdorf-West in 1932. Von Braun dreamed of conquering outer space with rockets and did not initially see the military value in missile technology.
During the Second World War, General Dornberger was the military head of the army's rocket program, Zanssen became the commandant of the Peenemünde army rocket center, and von Braun was the technical director of the ballistic missile program. They led the team that built the Aggregate-4 (A-4) rocket, which became the first vehicle to reach outer space during its test flight program in 1942 and 1943. By 1943, Germany began mass-producing the A-4 as the Vergeltungswaffe 2 ("Vengeance Weapon" 2, or more commonly, V2), a ballistic missile with a 320 kilometers (200 mi) range carrying a 1,130 kilograms (2,490 lb) warhead at 4,000 kilometers per hour (2,500 mph). Its supersonic speed meant there was no defense against it, and radar detection provided little warning. Germany used the weapon to bombard southern England and parts of Allied-liberated western Europe from 1944 until 1945. After the war, the V-2 became the basis of early American and Soviet rocket designs.