| Borommarachathirat I พระบรมราชาธิราชที่ ๑ | |||||
|---|---|---|---|---|---|
| King of Ayutthaya | |||||
 Portrait of King Borommarachathirat I of Ayutthaya on display at Suphan Buri National Museum (พิพิธภัณฑสถานแห่งชาติ สุพรรณบุรี) | |||||
| King of Siam | |||||
| Reign | 1370–1388 | ||||
| Predecessor | Ramesuan | ||||
| Successor | Thong Lan | ||||
| Born | 1310 | ||||
| Died | 1388 | ||||
| Issue | Thong Lan | ||||
| |||||
| House | Suphannaphum Dynasty | ||||
King Borommarachathirat I or King Borom Rachathirat I (Thai: สมเด็จพระบรมราชาธิราชที่ ๑), also known as Khunluang Pha Ngua (Thai: ขุนหลวงพะงั่ว); 1370–1388), was the third king of Ayutthaya Kingdom.[1]: 29 He was the older brother of King U-thong's consort, and was King Ramesuan's uncle.
As the lord of Suphanburi, a powerful rival of Ayutthaya, he forced King Ramesuan from power and took the throne of Ayutthaya. Known as a great warrior, his reign marked the expansion of Ayutthaya to the north. He suppressed a rebellion in Sukhothai Kingdom (1371–78) and subjugated major northern powers such as Phitsanuloke. Invading Chiengmai, his forces were defeated and repulsed at the Battle of Sen Sanuk, near Chiengmai.[2]
After his death in 1388, his son, Thong Lan reigned for only a week. Ramesuan, who had previously retreated to Lavo, returned and toppled him. Ramesuan eventually assumed the throne, as the king for the second time.