0 - Scientist decide the Earth is round, not flat. This is proven wrong when a sailor "falls" off the world and is never seen again.
1066 - King Harold inaugerates National Hysteria Day with his famous speech "Holy shit! It's the fucking Normans! AAAAAAAAA!"
1855 - An brief cease-fire is called in the Crimean War until Lord Raglan gets his sobbing under control.
1929 - Dozens of stockbrokers and bankers leap out of windows in wild National Hysteria Day celebration.
1966 - AustralianPrime Minister Sir Robert Menzies celebrates the nine hundredth anniversary of National Hysteria Day by running around in circles, screaming.
1986 - Copious amounts of vodka-induced partying causes several employees of the Chernobyl nuclear power plant to hysterically panic when the reactor can't handle the sound system. They take out a few control rods to compensate the drain on the power grid.
1990 - Media outlets report the outbreak of a deadly virus in the United States. Thirty-eight people die of panic attacks from the announcement, and two people are killed by the virus itself.