There’s a bit of just survivor bias when you think about these things.
When you hear detailed historical accounts its usually because its something that would have been recorded many times and we found a lot of things about it. So we know about Julius Caesar and Alexander the Great and Xerxes and the Three Kingdoms in China and the Kahn Mogolian empire etc…
But pick some random place or person and its very unlikely we know much about it.
Naram-Sin was the 37th King of Assyria… should be an important person, we know his name because he’s on a list of kings. We know he was the former king’s son…and that’s about it, we don’t even know when he reigned or anything he did.
When we do know its usually a case of preserved documents and contemporary kingdoms around the area also making note of it.
When there’s a new Roman Emperor, you’ll probably find records mentioning it from Persia to Portugal.
You only hear about the parts we know, we don’t know the vast majority of it.
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