According to Held, the idea for the conspiracy theory formed in his mind at a student party while speaking to an avid reader of New Age magazines, and from a car journey past Bielefeld at a time when the exit from the Autobahn to it was closed.
[12][unreliable source] In November 2012, German Chancellor Angela Merkel referred to the conspiracy in public when talking about a town hall meeting she had attended in Bielefeld, adding: "... if it exists at all", and "I had the impression that I was there".
However, even ten years after the conspiracy started, the mayor's office still received phone calls and e-mails which claimed to doubt the existence of the city.
[8] On April Fools' Day in 1999, five years after the myth started to spread, the city council released a press statement titled Bielefeld gibt es doch!
In allusion to the origin of the conspiracy, the 800th anniversary of Bielefeld was held in 2014 under the motto Das gibt's doch gar nicht (Unbelievable!, literally That doesn't exist).
[1] In August 2019, the council offered to give €1 million to any person who could provide "incontrovertible evidence" of Bielefeld's nonexistence in an effort to increase interest in the city.