January 1st, 1000
Pope Sylvester the 2nd was one of several who brought popularity to this date by claiming it to be the Millennium Apocalypse at the end of the Christian Millennium. The turn of the millennium was a big deal long before Y2K. The year 999 proved to be an interesting one for many as those that prepared for the end of the world willingly gave away their possessions, assuming that, with the world ending and all, there would be no need for them. Prisoners were set free, crops were neglected, and riots broke out as societies tried to handle the thought of the second coming of Christ. Come January 2nd, 1000, when Christ did not show, theorists changed their tune, stating that the end was really going to be on January 1st, 1033, which marked 1,000 years after his death.