Sputnik and Vostok
The Soviet space program was tied to the USSR's Five-Year Plans and from the start was reliant on support from the Soviet military. Although he was "single-mindedly driven by the dream of space travel", Korolyov generally kept this a secret while working on military projects—especially, after the Soviet Union's first atomic bomb test in 1949, a missile capable of carrying a nuclear warhead to the United States—as many mocked the idea of launching satellites and manned spacecraft. Nonetheless, the first Soviet rocket with animals aboard launched in July 1951; the two dogs were recovered alive after reaching 101 km in altitude. Two months ahead of America's first such achievement, this and subsequent flights gave the Soviets valuable experience with space medicine.
Because of its global range and large payload of approximately five tons, the reliable R-7 was not only effective as a strategic delivery system for nuclear warheads, but also as an excellent basis for a space vehicle. The United States' announcement in July 1955 of its plan to launch a satellite during the International Geophysical Year greatly benefited Korolyov in persuading Soviet leader Nikita Khrushchev to support his plans in January 1956, in order to surpass the Americans. Plans were approved for Earth-orbiting satellites (Sputnik) to gain knowledge of space, and four unmanned military reconnaissance satellites, Zenit. Further planned developments called for a manned Earth orbit flight by 1964 and an unmanned lunar mission at an earlier date.
After the first Sputnik proved to be a successful propaganda coup, Korolyov—now known publicly only as the mysterious "Chief Designer of Rocket-Space Systems"—was charged to accelerate the manned program, the design of which was combined with the Zenit program to produce the Vostok spacecraft. Still influenced by Tsiolkovsky—who had chosen Mars as the most important goal for space travel—in the early 1960s the Russian program under Korolyov created substantial plans for manned trips to Mars as early as 1968 to 1970. With closed-loop life support systems and electrical rocket engines, and launched from large orbiting space stations, these plans were much more ambitious than America's goal of landing on the moon.
Read more about this topic: Soviet Space Program