Wat Raeng is mentioned in the Royal Chronicles of Ayutthaya and is notorious in Siam's history.
It was in this area that the usurper king Worawongsathirat and his queen were killed in 1548 CE by Khun Phirenthorathep, the Head of the right division of the major guard. The story goes as follows:
Prince Yot Fa was the oldest son of King Chairacha (reign 1534-1547) and succeeded the throne. Due to his young age, he could not manage the Royal affairs and Prince Thianracha and Tao Sri Sudachan, King Chairacha's non-royal concubine, acted as regents. Some conflicts between the latter two arose, and Prince Thianracha entered the monkhood at Wat Ratcha Praditsathan, leaving the State affairs to Tao Sri Sudachan. The last committed adultery and, with intrigues, arranged that her lover (with the title Worawongsa) became Regent. It was then that Queen Regent Si Sudachan hatched a plan to place her lover, Khun Worawongsa, who was only a minor palace official, on the throne. They poisoned Prince Yot Fa in June 1548 CE and declared Khun Worawongsa the new king, further consolidating power by executing the nobles that dared to voice disapproval. Despite these measures, Worawongsa’s short reign would last only six weeks.
Khun Phirenthorathep, a descendant from the House of Sukhothai, disagreed with the usurpation of the throne by Worawongsa. Phiren held a secret meeting with some trustees, Khun Inthorathep, Mun Ratchasena, and Luang Si Yot and decided to put Prince Thianracha on the throne. They consulted an oracle at the recitation hall of Pa Kaeo Monastery (present Wat Yai Chai Mongkhon), which favoured Thianracha. Early January 1549 CE, Worawongsa announced his intention to proceed by boat to the Elephant Kraal to see a very large elephant caught. Phiren initiated the Governors of Sawankhalok and Phichit into his plan. The royal barge of Khun Worawongsa and Queen Sri Sudachan was intercepted in a narrow creek of the Ban Pla Mo Canal, leading to the corral. The usurper King and his Queen were dragged ashore and beheaded, together with their infant daughter. Their bodies were impaled near the ambush at Wat Raeng.
The execution of King Worawongsathirat and his queen was thus far from royal. At that time, the custom was to put the condemned in a red velvet bag and deliver them a fatal blow with a sandalwood club, preventing royal blood from touching the ground and the corpse from being seen or directly touched. Both, their royal status being in doubt and contrary to the principle, were immediately beheaded, a fast and effective way to get done with. The public display of the impaled bodies was classic for that time as a warning to all followers.
The brick mound is in geographical coordinates: 14° 22' 4.53" N, 100° 33' 37.97" E.
Footnotes:
(1) Khlong Ban Pla Mo is a defunct canal in the northern area, off the city island, running in the Khlong Sra Bua Sub-district of Ayutthaya. The waterway is mentioned in the Royal Chronicles of Ayutthaya in the vicinity of Wat Raeng. I believe the canal connected Khlong Sra Bua and Khlong Pha Lai. The mouth on the east was likely between Wat Raeng and Wat Laiso and on the other side opposite Wat Kamphaeng. It remains my guess. The canal was named after common species of fish in the Siamese waters of different genera.
(2) Thung Kaeo, or Crystal Field, is an area north of the city of Ayutthaya bordered on the west and north by Khlong Sra Bua, on the east by Khlong Hua Ro, and on the south by Khlong Mueang.
(3) Khlong Pha Lai, or the Canal of the Patterned Cloth, was a canal situated off the city island in the northern area running partly in present Tha Wasukri and Khlong Sra Bua sub-districts. The canal is defunct, but there are still some stretches existing from this canal. Most of the waterway, though, has been filled up. Khlong Pha Lai had its mouth west of Wat Mai and ran adjacent to Khlong Sra Bua into the old Lopburi River, a stretch of water called today Khlong Mueang.