The N1/L3 (from - Raketa-nositel', "Carrier Rocket"; Cyrillic: 1) was a super heavy-lift launch vehicle intended to deliver payloads beyond low Earth orbit. The N1 was the Soviet counterpart to the US Saturn V and was intended to enable crewed travel to the Moon and beyond, with studies beginning as early as 1959. Its first stage, Block A, remains the most powerful rocket stage ever flown. However, all four first stages flown failed mid-flight because a lack of static test firings meant that plumbing issues and other adverse characteristics with the large cluster of thirty engines and its complex fuel and oxidizer feeder system were not revealed earlier in development.The N1-L3 version was designed to compete with the United States Apollo program to land a person on the Moon, using a similar lunar orbit rendezvous method. The basic N1 launch vehicle had three stages, which were to carry the L3 lunar payload into low Earth orbit with two cosmonauts. The L3 contained one stage for trans-lunar injection; another stage used for mid-course corrections, lunar orbit insertion, and the first part of the descent to the lunar surface; a single-pilot LK Lander spacecraft; and a two-pilot Soyuz 7K-LOK lunar orbital spacecraft for return to Earth.

The N1-L3 was underfunded and rushed, starting development in October 1965, almost four years after the Saturn V. The project was badly derailed by the death of its chief designer Sergei Korolev in 1966. Each of the four attempts to launch an N1 failed, with the second attempt resulting in the vehicle crashing back onto its launch pad shortly after liftoff and causing one of the largest artificial non-nuclear explosions in human history. The N1 program was suspended in 1974, and officially canceled in 1976. All details of the Soviet crewed lunar programs were kept secret until the USSR was nearing collapse in 1989.

The Space Race was a 20th-century competition between two Cold War adversaries, the Soviet Union and the United States, to achieve superior spaceflight capability. It had its origins in the ballistic missile-based nuclear arms race between the two nations following World War II. The technological advantage demonstrated by spaceflight achievement was seen as necessary for national security, and became part of the symbolism and ideology of the time. The Space Race brought pioneering launches of artificial satellites, robotic space probes to the Moon, Venus, and Mars, and human spaceflight in low Earth orbit and ultimately to the Moon.The competition began in earnest on August 2, 1955, when the Soviet Union responded to the American 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 developments in ballistic missile capabilities made it possible to take the competition between the two states into space. This competition gained public attention with the "Sputnik shock", when the USSR achieved the first successful artificial satellite launch on October 4, 1957 of Sputnik 1, and subsequently when the USSR sent the first human to space with the orbital flight of Yuri Gagarin on April 12, 1961. The USSR demonstrated an early lead in the race with these and other firsts over the next few years, reaching the Moon for the first time with the Luna programme by employing robotic missions.

After US president John F. Kennedy raised the stakes by setting a goal of "landing a man on the Moon and returning him safely to the Earth", both countries worked on developing super heavy-lift launch vehicles, with the US successfully deploying the Saturn V, which was large enough to send a three-person orbiter and two-person lander to the Moon. Kennedy's Moon landing goal was achieved in July 1969, with the flight of Apollo 11, a singular achievement considered by the Americans as overshadowing any combination of Soviet achievements that have been made. However, such an opinion is generally contentious, with others attributing the first man in space as being a much larger achievement. The USSR pursued two crewed lunar programs, but did not succeed with their N1 rocket to launch and land on the Moon before the US, and eventually canceled it to concentrate on Salyut, the first space station programme, and the first time landings on Venus and on Mars. Meanwhile, the US landed five more Apollo crews on the Moon and continued exploration of other extraterrestrial bodies robotically.

A period of détente followed with the April 1972 agreement on a co-operative Apollo–Soyuz Test Project (ASTP), resulting in the July 1975 rendezvous in Earth orbit of a US astronaut crew with a Soviet cosmonaut crew and joint development of an international docking standard APAS-75. Being considered as the final act of the Space Race, the competition would only gradually be replaced with cooperation. The collapse of the Soviet Union eventually allowed the US and the newly founded Russian Federation to end their Cold War competition also in space, by agreeing in 1993 on the Shuttle–Mir and International Space Station programs.