There are few things you'd like written as the "cause of death" on your death certificate less than "toilet disaster" (I'd assume, I really don't know you that well). But that is what happened to between 60 and 100 nobles in 12th century Erfurt, Germany, who drowned in a toilet surrounded by people they actively disliked.
In July 1184, according to an account of the disaster, the Archbishop of Mainz (aka Conrad of Wittelsbach), and Ludwig III (aka the Landgrave of Thuringia) were in conflict.
It's not known what they were fighting about, but it had escalated enough that King Heinrich VI felt he needed to get involved. He ordered a meeting of a large number of nobles and high-ranking officials, setting the meeting place (though it is disputed, and could have happened elsewhere) of St. Peter’s Church in Erfurt.
Now, as a king, you'd probably expect that venue flooring wasn't his biggest concern, and you'd be right. In fact, it appears that nobody really looked into the toilet situation, either.
Heinrich, by way of foreshadowing, was a fan of using a phrase along the lines of “if I fail, so may I die in excrement" – which was especially relevant in this situation as beneath the meeting floor was a cesspool which a good number of the gathered nobles were about to drown in.
The floor gave way, possibly due to the weight of armor and chainmail worn by those gathered, which aren't exactly known for their buoyancy in water or human excrement. And so, 60-100 people drowned in monk excrement and pee, with some being fortunate enough (in this instance) to merely die via falling infrastructure.
Fortunately for the main people involved in the dispute, they had moved to another room to have a separate talk about the matters at hand, and escaped having the history books record that they drowned in poop.