Prasat Thong

Prasat Thong
ปราสาททอง
King of Ayutthaya
Idol of deified Prasat Thong in the shrine dedicated to him at the Bang Pa-In Royal Palace, built c. 1872–1876.
King of Siam
Reign1629 – 8 August 1655
PredecessorAthittayawong
SuccessorChai
Bornc. 1599
Died8 August 1655 (aged approx. 56)
SpouseSirithida
Issue
  • Chai
  • Narai
  • Traiphuwanathittayawong
  • Thong
  • Intharacha
  • Aphaiyathot
  • Noi
  • Yothathip
Names
Sanphet V
HousePrasat Thong
FatherOkya Sithammathirat

Prasat Thong (Thai: ปราสาททอง, pronounced [prāː.sàːt.tʰɔ̄ːŋ]; c. 1599–1655; reigned 1629–1655) was the founder and first monarch of the Prasat Thong dynasty, the fourth ruling house of the Ayutthaya Kingdom. Formerly a high-ranking official known as Okya Kalahom (Thai: ออกญากลาโหม), he rose to prominence during the reign of King Songtham by assisting in the suppression of a rebellion led by the king's son, Phra Sisin, in collaboration with the Japanese mercenary leader Yamada Nagamasa. Following a series of succession crises after Songtham's death, he seized power in 1629, briefly installing the infant Athittayawong as a puppet king before executing him and ascending the throne himself. His reign was marked by the reassertion of Siamese authority over Cambodia, though it also saw a weakening of Ayutthaya's control over its northern principalities.