Astronaut
The first civilian in space was Valentina Tereshkova aboard Vostok 6 (she also became the first woman in space on that mission).
Tereshkova was only honorarily inducted into the USSR's Air Force, which did not accept female pilots at that time. A month later, Joseph Albert Walker became the first American civilian in space when his X-15 Flight 90 crossed the line, qualifying him by the international definition of spaceflight. Walker had joined the US Army Air Force but was not a member during his flight. 
The first people in space who had never been a member of any country's armed forces were both Konstantin Feoktistov and Boris Yegorov aboard Voskhod 1.
Sally Ride
Sally Kristen Ride (May 26, 1951 – July 23, 2012) was an American astronaut, physicist, and engineer. Born in Los Angeles, she joined NASA in 1978 and became the first American woman in space in 1983. Ride was the third woman in space overall, after USSR cosmonauts Valentina Tereshkova (1963) and Svetlana Savitskaya (1982). Ride remains the youngest American astronaut to have traveled to space, having done so at the age of 32. After flying twice on the Orbiter "Challenger", she left NASA in 1987. She worked for two years at Stanford University's Center for International Security and Arms Control, then at the University of California, San Diego as a professor of physics, primarily researching nonlinear optics and Thomson scattering. She served on the committees that investigated the "Challenger" and "Columbia" space shuttle disasters, the only person to participate in both. Ride died of pancreatic cancer on July 23, 2012.