Trai Phum Phra Ruang

Trai Phum Phra Ruang (Thai: ไตรภูมิพระร่วง; lit. "Three Worlds According to King Ruang") is a 14th-century Thai Buddhist cosmological treatise attributed to King Lithai. Written around 1345 CE, it is considered the oldest known work of Thai literature and played a central role in shaping Siamese religious thought and kingship ideology.

The text reflects many beliefs of the Thai people, such as descriptions of hells, heavens, rebirth, the four continents (such as Jambudvīpa), kalpa, the kali yuga, the final age of the world, the coming of Metteyya, and the universal monarch. Trai Phum Phra Ruang is among the oldest known works of Thai literature and was widely illustrated in murals on the walls of Buddhist temples since ancient times.