The Historian Sima Qian

The Records of the Grand Historian iwas written by the historian Sima Qian more than 2,000 years ago.

It is theconsidered to be one of the world's greatest historical and literary masterpieces and an immortal document document that continues to have relevance today.

"Immortal" is a bit unusual here, I don't think it's applied that often to objects.

At ten years old, the boy moved with his father to the capitalto the capital with his father, where he received an education.

And at the age of 20, he was appointed asto the role of Palace Attendant whose. His duties were to inspect different parts of the country together with the emperor.

Since the Emperor Wu was fond of travelling around his empire, Sima Qian was given an opportunity to begin an extensive tour to almost every part of the country.

Thanks to his excellent writing skills, he pieced together fragmentary materials and in a sertudious manner, recorded anecdotes of celebrities of his time.

Then theHis final work has become an important material of historical studies and a valuable reference for historians.

Since these two things ("material for historical studies" and "valuable reference for historians") are quite similar, I would simplify it by just saying one :)