Emperor Xiaowen of Northern Wei
Despite Fang's high status, little is firmly established about his career except for the time that he served as chancellor—as, unusual for a chancellor, he did not have a biography in either the "Old Book of Tang" or the "New Book of Tang". It is known that his clan traced its ancestry to the early Jin Dynasty (266–420) official Fang Qian (房乾), who was sent as an emissary to the Xianbei but was detained and not allowed to return to Jin, whose descendants then took the Xianbei surname Wuyin (屋引) and followed the rulers of Northern Wei back south. They then changed their name back to Fang when Emperor Xiaowen of Northern Wei changed Xianbei names to Han names in 496 and settled in the Northern Wei capital Luoyang. Fang Rong's ancestors served as officials in Northern Wei and succeeding dynasties Northern Qi, Sui Dynasty, and Tang Dynasty, with Fang Rong's father Fang Xuanji (房玄基) serving as a low level official at the department of the treasury.