Why Did Ancient Empires Fall?

Like I'm 5: Empires are like big, strong kingdoms that rule over many people. But even the strongest ones can fall if things go wrong. Sometimes there aren't enough food or water to go around. Other times, enemies attack from all sides. Or maybe the leaders get tired of fighting and make bad choices. It's like when a big tower falls because one brick is missing, the whole thing crashes down.

• People might stop working hard if they don't get enough to eat.
• If enemies keep attacking, it can wear out an empire’s soldiers.
• Leaders making bad choices can cause trouble for everyone.