Yi Yuanji (c. 1000, Changsha, Hunan – c. 1064) was a Northern Song Dynasty painter, famous for his realistic paintings of animals. According to Robert van Gulik, Yi Yuanji's paintings of gibbons were particularly celebrated. He spent months roaming the mountains of southern Hubei and northern Hunan, watching roebucks and gibbons in their natural environment.

In 1064, Yi Yuanji was invited to paint screens in the imperial palace. Once this job has been completed, the Yingzong Emperor, impressed, commissioned him to paint the "Picture of a Hundred Gibbons", but unfortunately the artist died after painting only a few gibbons.

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