What happened
Following a siege of roughly 14 months, the Burmese armies of the Konbaung dynasty took the city on April 7, 1767. Ayutthaya was burned: palaces, temples, archives and much of Siam’s written record were destroyed, and tens of thousands of people, including members of the royal family, were deported to Burma. King Ekkathat died as the city fell; accounts of the circumstances vary.
Background
The invasion was part of the Konbaung dynasty’s expansion. A first invasion in 1760 was aborted; in 1765 King Hsinbyushin launched a two-pronged invasion whose armies converged on the capital. Factionalism at the Ayutthayan court, as commonly assessed, weakened the defense.
Consequences
The 416-year kingdom ended, and Siam briefly fragmented into regional power groups. The Burmese soon withdrew most of their forces to face Qing invasions of Burma (1765–69), easing Taksin’s reunification of Siam from Thonburi. The loss of records still shapes Thai historiography, and the political center moved permanently downriver — first to Thonburi, then to Bangkok.