Jia has interviewed royal family members like Pu Yi's younger sister Yun He and younger brother Pu Jie. His prize-winning work, The Extraordinary Life of the Last Emperor. Photos provided to China Daily

"Many just could not believe that a 37-year-old man with only middle-school education could have written such a book," Jia says.

He began a tedious process of contacting each and every person he had interviewed to give him a testimony.

With more than 30 such testimonies, Jia won the case after almost two years of court battles.

If his interviews of more than 300 people in a decade taught him how hard it was to write a book, his victory in the marathon copyright trial boosted his self-confidence and made him realize the importance of getting hold of exclusive material and historical records.

The interviews Jia conducted and the first-hand historical documents, facts and relics he has collected in the past four decades made him an expert on the country's last royal family.

In his own archives, he keeps nearly 1,000 photos related to the last emperor's family, hundreds of hours of discs about his interviews with family members and documentaries he made about some historical figures of the late Qing Dynasty.

With these, he has uncovered some stories that were never known before and also rectified some hearsay.

Pu Yi was born on Jan 14 of the lunar calendar in 1906, while Emperor Daoguang died on the same day in 1850. To avoid bad luck and also show respect for the late emperor, his birthday was said to be one day earlier. So his birthday was celebrated on Jan 13 every year.

There was a saying that Pu Yi's father said "kuai wan le (almost finished)" when young Pu Yi cried at the ceremony to crown him emperor. Even Pu Yi himself wrote in his biography that his father said "kuai wan le". The Chinese character "wan" was later interpreted as portending the end of the Qing Dynasty.

But, Pu Yi's younger sister told Jia that her father never said that. What he said was kuai hao le which also means "finish soon". But the character "hao" does not carry the ominous meaning.

Retired, Jia is still immersed in the study of the royal family. He says that he doesn't consider himself talented but he is obstinate in pursuing what he believes is worth his effort.

Contact the writer at [email protected].