Abstract

The Thai–Malay Peninsula is a multicultural region in Southeast Asia with a long history spanning at least 2,300 years. However, its sparse historical evidence makes its history discontinuous both in temporal and spatial regimes. This study utilized a multidisciplinary approach by combining astronomy, geography, and linguistics to geolocate maritime cities and geographical features in the Thai–Malay Peninsula from the eleventh to the seventeenth centuries CE. Astronomical computation results suggest that Arab sailors used two different systems to measure the angle of the Pole Star: one along the coastline of the Andaman Sea and Malacca Strait, and another for the Gulf of Thailand and the South China Sea. Etymological analysis results indicate that most native toponyms were transcribed into different languages. Some of them can be combined to reconstruct their continuation. This knowledge also solves some longstanding issues of the Thai–Malay Peninsula’s history and anthropology.