The book Historical Records was written by Sima Qian from the beginning of Three Emperors and Five Emperors. Writing history two or three thousand years ago, modern people can still do it, because we have archaeologists and various documents, but how did Sima Qian do it? Moreover, when Qin Shihuang unified the world, he burned books and buried Confucianism, leaving only the history books of Qin State, and then Xiang Yu burned Epang Palace, and many history books were also burned. Therefore, many people doubt the authenticity of Historical Records. In fact, the content of Historical Records is still very authentic.
However, Qin Shihuang didn't burn all the historical materials, but only the ancient historical books before the vassal states, and the historical books of the Western Zhou Dynasty, Shang Dynasty, Xia Dynasty and the Three Emperors and Five Emperors were not burned. Moreover, after the reunification of Qin Shihuang, many scholars were ordered to write "Lu Chunqiu", which also made a lot of efforts in historical records.
Sima Qian himself came from a family of historians. Although there is still a lot of controversy about this matter, Sima Tan, Sima Qian's father, is really an official of the Han Dynasty, and his job is to compile the history of the country. With his own father, it is also very possible that Sima Qian can read all the history books of the royal family. According to the historical materials mastered by Sima Qian, there is a great possibility to write the book Historical Records. Not only books, but also Sima Qian traveled all over the country. In the process of traveling, he learned the geographical features of historical events and experienced the scenes at that time. Also obtained a lot of folk historical materials and legends.
Although Sima Qian lived three thousand years after the Three Emperors and Five Emperors, according to the information he obtained, he should have obtained the most historical information in his time, and Historical Records was also the closest to historical facts.