The phrase "All your base are belong to us" is an old gaming meme that went viral circa 2000 (specifically, via the forums on Something Awful). It comes from the opening cut scene of the video game Zero Wing, in which the original Japanese script was translated into really bad "Engrish."

A more correct translation would be "We have taken over all of your bases," or "All of your bases have been taken over by CATS" (the antagonists in the game). Naturally, because the translation was so ridiculously bad, gamers around the world made a huge joke of it, with variations of the phrase still appearing in pop culture references to this day.