Alien Invaders of the DC Comics universe first appeared in Armageddon: The Alien Agenda #1. The comic depicted a race of aliens stranded on Earth millions of years ago only to have Earth colonized. Their leader Prime-One teamed up with Monarch. After Captain Atom took their time traveling Orb, their warriors followed him through time with Monarch.
Justice League (animated)
'Alien Invaders' is also the placeholder name given to the aliens in the first Justice League episode "Secret Origins". The Invaders are shapeshifting white humanoids resembling the White Martians, who invaded J'onn J'onzz's homeworld Mars and nearly did so with Earth. They are led by a Lovecraftian, jellyfish-like figurehead called The Imperium.
References
Invaders (DC Comics) Wikipedia(Text) CC BY-SA