|Major Gagarin spent two years training for his space trip
|1961: Russians win space race
Russia has beaten the USA in the race to get the first man into space.
At just after 0700BST, Major Yuri Alexeyevich Gagarin was fired from the Baikonur launch pad in Kazakhstan, Soviet central Asia, in the space craft Vostok (East).
Major Gagarin orbited the Earth for 108 minutes travelling at more than 17,000 miles per hour (27,000 kilometres per hour) before landing at an undisclosed location.
The Soviet leader Nikita Khrushchev has congratulated Major Gagarin on his achievement.
He sent the cosmonaut a message from his holiday home on the Black Sea.
"The flight made by you opens up a new page in the history of mankind in its conquest of space," Mr Khrushchev said.
The Russian news agency, Tass, made the first official announcement of Major Gagarin's flight at just before 0800BST.
Radio Moscow then interrupted its schedule to give details to a jubilant nation.
Major Gagarin's safe return has laid to rest worries that space flight would be fatal for humans.
It is also a blow to the Americans who had hoped to be the first to launch a man beyond Earth's atmosphere.
However, President Kennedy has congratulated the Russians on their achievement.
It would be some time before the United States caught up with the Russians in the fields of rocket boosters, the president added.
Rumours that a Russian launch attempt was imminent began some days ago.
It was the culmination of two years of highly secretive training for Yuri Gagarin, 27, who beat off thousands of other hopefuls.
The previously obscure army major has returned to earth a national hero.
He has already been awarded the title of "Master of Radio Sport of the Soviet Union" and a big reception for him at the Kremlin in Red Square is being planned.