The Chozo were an ancient, mysterious and highly advanced species of the Metroid Universe. Countless ruins and technological wonders are littered throughout the galaxy. They are responsible for the creation of both the Metroids and Mother Brain - an ill-tempered AI that would eventually lead the Space Pirates. These would both later pose a threat to galactic civilization.
The Chozo have a long history of making contact with other races like the humans, and sharing their technology, wisdom, and culture.