In 1562, 23 Huguenots were killed in the Massacre of Vassy, which kicked off the French Wars of Religion. Between two and four million people got to find out if their particular beliefs were correct before the dust settled 36 years later. That represented between 12.5 to 25 percent of the entire population of France at the time. To put that in perspective with the current population of the US, a similar war would result in between 40 and 80 million deaths.
So keep this sort of thing in mind when you hear about people wanting to establish national religions anywhere. That shit never ends well.