The Sagittarians arrived on Earth an unknown number of years ago and planted their Planet Destroyer machine within the Savage Land. The Swamp Men worshiped them as Gods and the aliens left the natives a giant statue to worship. The statue turned out to be an android called Umbu who was brought to life by The Sagittarians when they were ready to destroy the world. Unfortunately for the would be conquerors, The Incredible Hulk happened to be around and along with Ka-Zar an Zabu, put an end to their plans. The aliens then kidnapped Bruce Banner who ironically ended up becoming their savior when The Hulk freed The Sagittarians enslaved race from The Galaxy Master.
The Sagittarians were created by Stan Lee and Herb Trimpe and first appeared in "Umbu, The Unliving" in 1968.