False prophets (or self serving scam artist demagogues) have always existed. So have gullible and greedy people that follow those demagogues. War, famine, disease and death were nothing new either. It's all just normal human behaviour, sadly enough.

One thing also leads to another: If a self serving demagogue gets too many followers, then it's going to lead to lawlessness and war, which are usually accompanied by famine and plagues, which result in lots of excess deaths. That situation is going to cause societal upheaval and maybe even a societal collapse, which the incumbent powers didn't want, so they created cautionary tales to hopefully teach the people how to recognize demagogues, to prevent those from getting too many followers in the first place.