St. John's Dance
St. John's Dance (known as Johannistanz or Johannestanz in Germany) was the medieval name for a phenomenon which emerged during the time of the Black Death. The medical term is chorea imagnativa aestimative. Basically, it is a form of apraxia expressing itself as "dancing rage," as uncontrolled ecstatic body movements. In the eyes of the church, those suffering from St. John's Dance were possessed by the devil.
The following excerpt (translated form the German) describes a bit of detail surrounding St. John's Dance:
"This dancing rage doubtlessly had no organic reasons but was caused by mass hysteria breaking out as a result of fear of the Black Death. It started in Aachen [Germany] in 1374 and spread over large parts of Europe. It was Germany where this phenomenon was called 'St. Johannestanz' [St. John's Dance] first. John the Baptist was the patron saint against epilepsy and other kinds of apraxia. The 'dancing epidemic' received its name as an expression for the hope for healing. Later, 'St. John's Dance' was renamed 'St. Vitustanz' or 'Veitstanz' [St. Vitus' Dance], because of a legend about St. Vitus, a Sicilian youth who died during the anti-Christian pogroms of the 4th century. According to this legend, St. Vitus had prayed to god to relieve all those from the dancing rage who fasted the evening before his dying day. The tradition claims that immediately after that a voice from heaven was heard saying: 'Vitus, your prayer are answered'. Thus St. Vitus became the patron saint of all those suffering from the dancing rage."
References
- Bezirkskrankenhaus Taufkirchen, Huntington Zentrum Süd (County
Hospital Taufkirchen, Huntington Center South), 'Chroea Huntington'
- A medical article on this topic (49 pages) is available here, but only in a German version: