Lin Jiulang's prototype is Li, the prime minister of Xuanzong in Tang Dynasty.

Li is a controversial historical figure, and his complex personality and behavior are fully reflected in Lin Jiulang in the TV series The Longest Day in Chang 'an.

In the 24th year of Kaiyuan (736), Li Fulin, the great grandson of cousin Li Yuan of Tang Gaozu, succeeded to the throne and became a famous prime minister. During Li's tenure, he was called a "sweet sword" for framing officials who might threaten his image. In addition, when Emperor Xuanzong of the Tang Dynasty abolished Shu Ren, the third prince, and killed them, he added fuel to the flames, even constantly trying to overthrow Prince Hengli, but all failed. In the eleventh year of Tianbao (753), Li, who died of illness, was falsely accused of rebellion by Yang, and his official property was cut. His coffin was split open, the beads were taken out of his mouth and his robe was taken off. He was buried in a small coffin as a gift from Shu Ren. After Su Zong ascended the throne, he even planned to dig Li's grave and burn his body, but Li Bi advised him to give up.