Phra Aphai Mani is a 48,700-line epic poem composed by Thai poet Sunthorn Phu, who is known as "the Bard of Rattanakosin". It is considered to be one of Thailand's national epics. With 48,686 couplets, it is listed as the longest Thai single poem. Suthorn Phu started working on this epic fantasy in 1822 and finished it in 1844; it took 22 years. It is also one of the most well-known Thai folklores that has been heavily adapted into films and comics. The main protagonists are Prince Aphai Mani, the mermaid, and the Pisue Samutra; a female ogress who can transmute herself into a beautiful girl.

Phra Sunthorn Vohara (Phu) (Thai: พระสุนทรโวหาร (ภู่), RTGS: Phra Sunthonwohan (Phu), pronounced [pʰá.sǔn.tʰɔ̄ːn.woː.hǎːn.pʰûː]; 26 June 1786 – 1855), known as Sunthorn Phu (Thai: สุนทรภู่, RTGS: Sunthonphu, pronounced [sǔn.tʰɔ̄ːn.pʰûː]), is Thailand's best-known royal poet. He wrote during the Rattanakosin period.