6. Collective Hysteria Sweeps Through a City
Milan’s mass poisoning panic started on the night of May 17, 1629, when some citizens reported seeing mysterious people placing what appeared to be poison in a cathedral partition. The city’s health officials went to the cathedral but found no signs of poisoning. The following morning, the Milanese woke up to an eerie discovery: all doors on the city’s main streets had been marked with a mysterious daub. When health officials inspected the daubs, they found nothing harmful in them.
The authorities concluded that the daubs were a prank by mischievous actors with a sick sense of humor, getting some laughs out of the citizens’ fears. Official reassurances were unavailing, however. Many Milanese, already on edge for months, took the mysterious daubs as a sign that the expected poison attack had finally arrived, and mass hysteria swept the city. As panic got a grip on the populace, the good people of Milan saw things that weren’t there and interpreted innocent acts in the most sinister ways possible.