founder and ruler of the kingdom of Sukhothai, the first independent Tai (Thai) state.

Bang Klang Hao headed a petty Tai principality near Sukhothai when, about 1245, he joined with another Tai leader, Pha Muang, to rebel against the governor of Sukhothai, who was a deputy of the Khmer kings of Angkor. The two seized nearby Sawankhalok, and Bang Klang Hao defeated the Khmer governor in personal combat before Sukhothai. Pha Muang then conferred his own royal Khmer title on Bang Klang Hao, who as Sri Indraditya now ruled independently. Over the ensuing century, Sukhothai grew and flourished as the preeminent Tai state of the region, particularly under Indraditya's second son, Ramkhamhaeng.