Simplify the following text for a Grade 9 native English-speaking person.
Original: Herodotus estimates that Homer lived 400 years before Herodotus ' own time , which would place him at around 850 BC ; while other ancient sources claim that he lived much nearer to the supposed time of the Trojan War , in the early 12th Century BC .
Simplified: Herodotus said that Homer lived 400 years before his own time , which would place him at around 850 BC ; but other ancient sources gave dates much closer to the time of the Trojan War .