The Phantom Time Hypothesis was introduced in 1991 by Heribert Illig. The idea is that certain periods of time, specifically those in Europe, didn't ever exist and it's just a massive cover-up. Illig thought it was possible through forgery and misrepresentation of artifacts and documents.

He specifically questioned the Middle Ages in Europe in AD 614-911. He is suspicious of the way they dated this period through systems called radiometric and dendrochronological methods of dating. He used the Roman type architecture present to fuel his hypothesis. There are discrepancies between the Julian calendar and the real calendar, too.

Thirteen days were unaccounted for once the Gregorian calender was implemented and the Gregorian calender was adjusted by ten days to make it all fit better. Illig saw this as another sign of cover-up and conspiracy. He estimated that three centuries were counted that never actually existed.

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