Tha Din Daeng campaign
The Tha Din Daeng campaign was a short military campaign that took place in 1786 at Tha Din Daeng in present-day Sangkhla Buri District, Kanchanaburi Province in western Thailand. The conflict occurred during the Burmese–Siamese War (1785–1786), and was fought between the Burmese forces of King Bodawpaya of the Konbaung dynasty and Siamese forces commanded by King Rama I of the Rattanakosin Kingdom, together with his brother Maha Sura Singhanat. The campaign represented Burma's renewed attempt to invade Siam following its defeat during the Nine Armies War, but the Siamese victory at Tha Din Daeng halted the advance and secured Siam's western frontier against further incursions.
Military Campaigns
Prelude
After many defeats in early 1786, King Bodawpaya retreated to Martaban. However, he retained some of his forces on the Tenasserim Coast waiting for the new campaigns. The traditional wars were usually conducted in dry season as the lands in the rainy season were swampy and ravaged with disease, making it unsuitable for marching and encampment. King Bodawpaya ordered the Burmese forces at Tavoy to retreat to Martaban under the command of Minhla Sithu, while Maha Thiri Thihathu was ordered to retreat from Mergui to Tavoy. The king then marched back to Dagon where he worshipped the famous Shwedagon Pagoda and returned to Ava. The Burmese armies stationed at Martaban and Tavoy, waiting for the rainy season to be over to conduct new invasions of Siam.In September 1786, King Bodawpaya resumed his Siamese campaigns. He sent his eldest son and heir, Prince Thado Minsaw or Prince Nanda Kyawdin to Martaban to organize the new invasion of Siam.
Preparations
Prince Nanda Kyawdin or Einshe Min Uparaja took the lead of the army of 50,000 men at Martaban, with Wundauk Nemyo Kyawzwa as his Sitke. King Bodawpaya made sure that the provision shortage would not hinder the campaign again. He ordered the grain rations of Arakan and the whole Lower Burma to be sent to the frontlines. The Burmese also established strong supply lines with supply outposts stationed all along the way from Martaban to Kanchanaburi. Unlike the previous invasion, the Burmese concentrate the forces in single direction at Kanchanaburi instead of dispersing the forces in many directions. Prince Nanda Kyawdin sent Minhla Sithu, the Burmese veteran who had been defeated by the Siamese at the Battle of Latya seven months earlier, to lead the vanguard of 30,000 ahead into Kanchanaburi.After King Rama I and Prince Maha Sura Singhanat received news of the Burmese advance, they ordered the mobilization of forces in Bangkok and the provincial towns. In late February 1786, they departed Bangkok by river with the royal flotilla, accompanied by the vessels of senior nobles and officials in full formation. The vanguard was placed under Prince Maha Sura Singhanat and Chao Phraya Rattanapiphit, consisting of about 30,000 troops drawn from the Grand Palace and the Front Palace, and was sent ahead. The main royal army followed with the Rear Palace and other princes, providing a further reinforcement of slightly over 30,000 men. Phraya Phonlaphop was ordered to remain in Bangkok to oversee the defense of the capital.
When the Siamese vanguard reached Sai Yok, the Front Palace commander ordered the forces of Chao Phraya Rattanaphiphit, together with the armies of Phraya Kalahom Ratchasena, Phraya Cha Saenyakon, and provincial levies—amounting to roughly 20,000 men—to disembark and advance overland with elephants, cavalry, and infantry forming the forward column. A reserve force of about 10,000 men followed under the command of the Prince Anurak Devesh. Upon reaching Tha Khanun, the main royal army left the flotilla and proceeded by land to support the reserve column.
The vanguard reached the Burmese encampment at Samsop and established several forward camps to encircle it. The Rear Palace's reserve then set up a royal camp roughly two kilometres behind the vanguard, while the main royal force established another camp about 2.8 kilometres further to the rear.
The battle
The Burmese army entered Kanchanaburi via the Three Pagodas Pass. Minhla Sithu divided his forces, establishing encampments at Tha Din Daeng and Samsop—both in what is now Sangkhlaburi—while Prince Nanda Kyawdin remained at the pass to secure communications and the line of retreat.After Siamese forces had consolidated their positions, King Rama I ordered both the Front Palace army under Prince Maha Sura Singhanat and the main royal army commanded by the king to detach troops to reinforce the vanguard and coordinate a concerted attack on the Burmese camps. The reinforcing columns from the Front Palace and the royal army were divided and dispatched toward the two Burmese positions at Tha Din Daeng and Samsop, enabling a simultaneous assault on both fronts. The Siamese then launched a general attack on all Burmese positions. Both sides exchanged sustained artillery and musket fire as Siamese troops advanced by digging approach trenches toward the fortifications. After three days of fighting, Siamese reinforcements stormed the defences, breached the encampments, and overran the Burmese positions. The Burmese abandoned their camps and retreated; Siamese troops pursued them, inflicting heavy losses and taking many prisoners.
When the Einshe Min, serving as commander of the royal Burmese army, learned of the defeat of the forward force, he ordered the main army to withdraw to Martaban without attempting to hold its position. Siamese troops pursued the retreating Burmese as far as the royal encampment, where they seized a large quantity of weapons. The Siamese king subsequently instructed officials to direct the vanguard to burn Burmese granaries and storehouses containing rice, dried fish, and other provisions throughout the area, before withdrawing and returning to Bangkok.
Aftermath
According to the contemporary account of Vincenzo Sangermano, a Catholic missionary residing in Burma at the time, news of Bodawpaya's defeat and withdrawal spread rapidly in the Burmese capital, provoking anxiety at court and among the populace, where fears arose that a continued Siamese pursuit might threaten Amarapura itself. A later interpretation by Sir Arthur Purves Phayre offers a contrasting perspective from Siam: Phayre eulogises King Phutthayotfa Chulalok as the ruler who rallied a population long cowed by Burma, restoring their confidence in the aftermath of the victory.Legacy
The Tha Din Daeng campaign also entered Thai literary memory. King Phutthayotfa Chulalok is credited with composing Nirat Tha Din Daeng, a long nirat poem written during the 1786 march to the western frontier. In the conventional nirat mode, it mixes personal yearning with a travel narrative of the army's route, before ending with an account of the fighting at Tha Din Daeng.The campaign is commemorated by a park established by the Royal Thai Army about from the town of Kanchanaburi.