The phantom time hypothesis is a historical conspiracy theory advanced by German historian and publisher Heribert Illig (born 1947) which proposes that the Anno Domini dating system was fabricated, adding in a period of "phantom time" in the Early Middle Ages, from AD 614 to 911. According to the hypothesis, events dated to this period in Europe and neighbouring regions either occurred in a different period, or did not occur at all.

The phantom time hypothesis is a historical conspiracy theory advanced by German historian and publisher Heribert Illig (born 1947) which proposes that the Anno Domini dating system was fabricated, adding in a period of "phantom time" in the Early Middle Ages, from AD 614 to 911. According to the hypothesis, events dated to this period in Europe and neighbouring regions either occurred in a different period, or did not occur at all.