Suphanburi

Suphanburi, older Suphannabhum, was a Thai mueang on the Tha Chin river west of the Chao Phraya plain. In 1337 its lord was Khun Luang Pha Ngua of the Suphannaphum line.

Pha Ngua helped U Thong found Ayutthaya in 1351, then seized its throne in 1370 as Borommarachathirat I. His dynasty briefly lost and regained the crown after 1388; the principality merged into Ayutthaya in 1438. At Nong Sarai in 1593, Naresuan killed the Burmese crown prince in an elephant duel, restoring Siamese independence.