This Day in History: 1374-06-24

St. Vitus Dance epidemic breaks out on this day in 1374 in Aachen, Germany and spreads throughout Belgium and the Netherlands. Dancers could not control themselves and sometimes danced for months on end, sometimes dying of exhaustion or heart attacks. Hundreds of people at a time might be affected. The dancing mania is well known in history with periodic outbreaks until the mid-20th century. Yet it is a mystery, and its cause may have involved mass poisonings from contaminated grain.   (Illustration: The Dancing Mania by Hendrick Hondius  1642)