But no advanced extraterrestrial technology was behind the move: according to a spokesperson for Facebook, the event was removed by "mistake".
The BBC reports that the founder of the group, Mathew Roberts, received a message on Saturday claiming that his tongue-in-cheek event broke Facebook's community standards - but that the social giant has now restored the group.
Roberts' event called for an army of memelords and alien fanatics to storm the Air Force base in the Nevada desert. The group's description: "Let's see them aliens."
Prior to being removed earlier this week, the tongue-in-cheek event convinced more than 2 million Facebook users to join the attack.
Area 51 has long been the subject of wild speculation — and plenty of memes as well. But in reality, the Air Force base has hosted hundreds of nuclear weapons tests and has served as testing grounds for a range of new stealth aircraft.
In the end, though, everything online eventually gets monetized.
Case in point: you can now buy official Storm Area 51 merchandise on a website linked in the event's description.