Subsequently the ideas of Communism gained ground in Cuba and many other countries.
After Stalin's death and a short period of collective leadership, a new leader Nikita Khrushchev denounced the cult of Stalin's personality and started the process of de-Stalinization. Gulag labor camps were abolished and a great many of prisoners released; the general easement of repressive policies became known later as Khruschev thaw.
In 1957 the Soviet Union launched the world's first artificial satellite, Sputnik 1, thus starting the Space Age, and the Russian cosmonaut Yuri Gagarin became the first human to orbit the Earth aboard Vostok 1 manned spacecraft on 12 April 1961. Tensions with the United States heightened when the two rivals clashed over the deployment of the U.S. Jupiter missiles in Turkey and Soviet missiles
Following the ousting of Khrushchev, another period of collective rule ensued, until Leonid Brezhnev established himself in the early 1970s as the pre-eminent figure in Soviet politics. Brezhnev's rule oversaw economic stagnation, since the reforms, attempted by the Prime Minister Alexey Kosygin, were stifled. Those reforms (see Kosygin reform) had been aimed into shifting the emphasis of the Soviet economy from heavy industry and military production to light industry and the production of consumer goods. However that would mean significant decentralization of economy and implementing capitalist-like elements, and the Communist leadership wouldn't accept this.
In 1979 the Soviet forces entered Afghanistan at the request of the existing communist government. The subsequent occupation drained economic resources and dragged on without achieving meaningful political results. Ultimately Soviet forces were withdrawn from Afghanistan in 1989 because of international opposition, persistent anti-Soviet guerilla warfare (enhanced by the U.S.), and a lack of support from Soviet citizens. Tensions rose between the U.S. and Soviet Union in the early 1980s, fueled by anti-Soviet rhetoric in the U.S., the ongoing Soviet occupation of Afghanistan, the SDI proposal, and the controversial downing in 1983 of Korean Air Lines Flight 007 by the Soviets west of Sakhalin near Moneron Island.
Prior to 1991, the Soviet economy was the second largest in the world, but during its last years it was afflicted by shortages of goods in grocery stores, huge budget deficits and explosive growth
Sergius of Radonezh blessing Dmitri Donskoi in Troitse-Sergieva Lavra, before the Battle of Kulikovo. A painting by Ernest Lissner.