No culture has done that really. You need to look at the sources of the prophesies. Josè Argülles is the one that started to claim that the Mayan had predicted the end of the world in 21-12-12 but, it's his own prophesy that he has no proof for. So, the culture didn't say it Josè Argülles did. While it's rather easy to track the origin of the Mayan prophesy back to Josè Argülles it's not so easy on other cases.
One such thing is Nostradamus, people keep claiming that he has made prophesies about the end of the world, and the keep changing the dates to fit their own idea. First it was this date then it was that date then it was 1999 and now it is 2012. Who's really behind it is really hard to find out since there are a lot of persons that study and believe in Nostradamus prophesies, even though he has never managed to foretell anything.
You also have Planet X or Nibiru. The origion of Nibiru can be traced back to the 70's and a book by Zacharia Sitchin called The 12th Planet, where the planet was named Marduk and it's moon was named Nibiru. Somewhere along the way the planet became Niburu instead of Marduk and that planet will bring the end of the world in 2012. It's hard to tell if it's Zacharia Sitchin that has breathed life into his old book to make more money on it or if it someone else that has used it to create a new prophesy.
