The first American astronaut, and the second person in space in general, was Alan Shepard, Jr. Like most of the early astronauts, Shepard was recruited into NASA from the Navy, where he was a test-flight pilot for high-altitude experimental craft. In the 1950s, he flew in the F3H Demon, F8U Crusader, F4D Skyray, and F11F Tiger, F5D Skylancer, logging over 8,000 hours of flying time with 3,700 hours in jet aircraft. Before he left to join NASA to become an astronaut, he was an instructor at Test Pilot School.

When the Space Race was in full swing in the late 1950s, NASA selected 110 military pilots to undergo a rigorous test regime to select out an elite group of seven for the USA's first manned spaceflights. This was part of the Mercury Project, and the elite group became known as the Mercury Seven, flying the historic series of Mercury missions. Trying to beat the Russians into space since Sputnik, the USA scheduled to have the pioneering astronaut Shepard go into space in October 1960, but the project was delayed due to the necessity of unplanned preparatory work.

On 12 April 1961, Soviet cosmonaut Yuri Gagarin became the first man in space, orbiting the Earth just once before landing again in the Soviet Union — but that was enough. Not only had the Soviets beaten the Americans by creating the first satellite, now they had launched the first human astronaut.

Only a few weeks later, on 5 May 1961, Shepard became the first American astronaut, launched into space on board the Freedom 7 capsule. Launched from Cape Canaveral, Florida, The capsule reached an altitude of 187 km (116 mi) and traveled in space for only 16 minutes before splashing down in the Gulf of Mexico. Unlike the Soviet launch, during the Freedom 7 flight, Shepard was in control of the craft the entire time.

The entire flight was played on TV and watched by millions. After successfully being recovered, Shepard was hailed as a national hero, being praised by the President and treated to parades in Washington, New York, and Los Angeles.