Ji is listed 345th in the Song dynasty classic text Hundred Family Surnames.

Luzhong's father Wuhui (吴回) was put in charge of fire by Emperor Ku and given the title of Zhu Rong.

A descendant of Dapeng (大彭), the third son of Luzhong, was enfeoffed in Ji 暨 (in modern Dongmocheng Township, Jiangyin, Jiangsu), and his descendants adopted Ji as their surname.

From Fugai (夫概), a younger brother of King Helü of the Kingdom of Wu, a major power of the Spring and Autumn period.

Fugai attempted to usurp the throne of Wu, but was defeated by Helü and fled to the Kingdom of Chu.