The Dominator invasion was the hostile attack on Earth-1's Earth by the alien race known as the Dominators who had the goal of wiping out the planet's meta-human populace along with the rest of all life on the planet. However, the various heroes of Earth-1, along with help from the alien super hero Supergirl who hailed from Earth-38, managed to repel the Dominators.
In the year 1951 on Earth-1, the Dominators landed on Earth, abducting humans to gather information about them. After President Ike Eisenhower waited for too long without action, the extraterrestrials attacked, killing hundreds of soldiers and capturing more. This was due to the emergence of the meta human super hero team the Justice Society of America. After this they simply left.