Yuri Gagarin was the first cosmonaut to travel into space. He was a Soviet pilot and cosmonaut who became the first human to journey into outer space, completing a single orbit of the Earth on April 12, 1961. Gagarin's flight was a major milestone in the Space Race between the Soviet Union and the United States. He was awarded the title of Hero of the Soviet Union and is remembered as one of the most influential figures in the history of space exploration.