![](https://i.imgur.com/SrmRVQ7.jpeg)
Dancing plague of 1518 where between 50-400 people took to dancing from July to September
The most prominent theory is that it was from the mould on their food.
Food was scarce - meaning they have eaten everything available. Even bad spoiled bread with mold. Which had LSA on it from ergot mushroom, precursor to LSD.