Lundakarnevalen started back in 1849 with a party organized by the Smalan nation (a student organization, often compared to fraternities). It resembled a typical Swedish "springfest" or Mayfest, even though this one happens every four years.
Every carnival has a directory board and a huge crowd of volunteers who prepare the topic for the event. The period of the carnival is as much fun as getting ready for it. The whole town lives for four years only with the carnival in mind!