Monthon were administrative subdivisions of Thailand at the beginning of the 20th century. The Thai word monthon is a translation of the word mandala (, literally "circle"), in its sense of a type of political formation. The monthon were created as a part of the thesaphiban (, literally "local government") bureaucratic administrative system, introduced by Prince Damrong Rajanubhab. Together with the monthon, today's present provinces (changwat), districts (amphoe), and communes (tambon) were established step-by-step throughout Thailand. Each monthon was led by a royal commissioner called thesaphiban (เทศาภิบาล), later renamed to samuhathesaphiban (สมุหเทศาภิบาล). The system was officially adopted by the 1897 Local Administration Act, after some monthon had been established and administrative details were sorted out.