I nominate 'The Records of the Grand Historian' by Sima Qian. It covers the beginning of Chinese history, to the first Dynasty (united mainland) of Qin 秦 and parts of Han 汉. Though it was completed in 109 B.C, what it known for is its absolutely unopiniated recording of the Emperors, or other people and events that were worthy of recording. He has recorded both the good deeds and the bads. But what is amazing is the perspective it offers- if Sima Qian could not personally verify a historical fact (sometimes he even travelled to the place it happened to see if he could discover more information) he would omit or note that he could not verify it. If there were two equally as likely possibilities, he sometimes would include both, in seperate chapters, and leave interpretation up to the readers. Even if a man was emperor, he was not guaranteed notice, and one or two sentences sufficed as an entry. Likewise, if a man was not an emperor but was supremely influential, no matter his birth, he would have his name down. No historian had his insight and fairness in recording a dynasty's history, and I think his work is worthy of being the greatest (I need to read all the others though to make a fair judgement).
Really interesting. Contemporary western historians (mostly Roman) often wrote hagiography because they were afraid of exile. And then there's Procopius, who wrote like six complimentary books about Justinian, but also wrote a secret book about how fucked up he was which only showed up several hundred years after they died.
He spoke up for a General who had surrendered (to barbarians I think), arguing the surrender was temporary and it was to preseve their army. Emperor did not like that. Emperor said, okay, Sima Qian. You either die, or you choose castration. Sima Qian chose castration (you could pay it off, but he didn't have the money to) so he could (again, I remember it had something about his father's goals) finish the book. So he does have a pretty good grudge against the royal family, but he still analyzes them fairly.