People write about earlier times by studying contemporary written sources and records and looking at archeology from the period. They also use later writers who

People write about earlier times by studying contemporary written sources and records and looking at archeology from the period. They also use later writers who had used and quoted contemporary sources. They also make inferences based on that material and syntheses of other material. In Herodotus's case, he used sources such as Thersander of Orchomenus, Archias of Sparta, and numerous other named and unnamed sources. He also made stuff up, but that's discouraged in modern history. There's an interesting chapter preview about his sources here: https://brill.com/view/book/edcoll/9789004217584/B9789004217584-s017.xml https://brill.com/view/book/edcoll/9789004217584/B9789004217... There's no guarantee that someone living in 1922 would be more accurate about what happened at that time than a historian writing today. They might have access to more detail, but they can lie, be mistaken, be partial, and so on. Eye witness testimony is often less reliable than a methodical examination of the available evidence, however later that happens.