Fall of the Sukhothai Kingdom (1430s)

Timeline

1. 1431–1435Sukhothai · ThailandSukhothai nominally retained its royal title, but diplomacy, military affairs, and tribute were controlled by Ayutthaya. Borommaracha II appointed his son Ramesuan as governor of Sukhothai, further hollowing out the local royal house.
2. 1438Sukhothai palace · Sukhothai ProvinceAround 1438 Ayutthaya formally abolished Sukhothai's independent royal title and brought the old capital under direct central rule. The last Sukhothai monarch's power was completely eliminated, and the kingdom ceased to exist as a political entity.
3. 1439–1440Northern Chao Phraya basin · ThailandAfter annexation, the old Sukhothai capital became Ayutthaya's northern administrative center; Buddhist architecture and stone-carving traditions were preserved, but sovereignty passed entirely to Ayutthaya, laying the foundation for later expansion.