Bible! Every single sentence of history in the Bible has anywhere from three to over 250 records found to confirm each line! Plus all the items and places in the Bible that are also still here.
OMG i loved animorphs when i was a kid. i read all the books, including the megamorphs and andalite chronicles. i was excited for the TV series but it freaked me out as a kid showing the yeerks going into people's heads.
i would probably say Harry Potter though. the way it goes along in the series adding more back story to each character that brings them all together in the finale is really good.