Which is the first human orbital space flight?

The first instance of humans flying to outer space was the Vostok 1 mission by the Soviet Union (Russia) in 1961 that carried the Russian astronaut Yuri Gagarin to outer space. The entire mission lasted about 108 minutes from launch to landing, completing an orbit around the earth. The Vostok mission initiated several space missions carrying humans to outer space, like the Apollo and Luna missions.