Okay, so a long time ago, there was something called the Late Bronze Age. It was a time when people had been around for a while and they had learned how to do lots of cool things like farm, make pottery, and trade with each other. But then, something really bad happened. It's like when you're playing with your toys and suddenly your little brother comes in and knocks them all over.
What happened was that many things went wrong at the same time. There were big earthquakes that made the ground shake and buildings fall down. There were also really bad droughts, which means there was not enough rain, so people couldn't grow crops and animals couldn't find food. And on top of that, there were probably also some wars between different cities and kingdoms.
All of these things happened so much and so fast that everyone got really scared and didn't know what to do. It was like a big puzzle with lots of pieces that people couldn't put back together. The kings and leaders who used to make the rules and keep everyone safe couldn't do it anymore. And things got really chaotic, which means lots of people were running around and doing whatever they wanted, without any plan or order.
So, the Late Bronze Age collapse was a time when lots of bad things happened all at once and no one could fix them. It was like when you try to build a tower with blocks, but then someone comes and pushes everything down.