An outbreak of dancing mania, in which crowds of people danced themselves to exhaustion, began in Aachen (in present-day Germany) before spreading to other parts of Europe.
Dancing mania
Dancing mania was a phenomenon that may have had biological causes, which occurred primarily in mainland Europe between the 14th and 17th centuries. It involved groups of people dancing erratically, sometimes thousands at a time. The mania affected adults and children who danced until, allegedly, they collapsed from exhaustion and injuries, and sometimes died. One of the first major outbreaks was in Aachen, in the Holy Roman Empire, in 1374, and it quickly spread throughout Europe; one particularly notable outbreak occurred in Strasbourg in 1518 in Alsace, also in the Holy Roman Empire.
Free Imperial City of Aachen
The Free Imperial City of Aachen, also known in English by its French name of Aix-la-Chapelle and today known simply as Aachen, was a Free Imperial City and spa of the Holy Roman Empire west of Cologne and southeast of the Low Countries, in the Lower Rhenish–Westphalian Circle. The pilgrimages, the Coronation of the Holy Roman Emperor, flourishing industries and the privileges conferred by various emperors made it one of the most prosperous market towns of the Holy Roman Empire.