Burmese–Siamese War (1662–1664)

Concurrent with the withdrawal of the Manchu from Burma and the return home of the Siamese from Lan Na, a revolution was taking place in the Toungoo capital, Ava. In June 1662, Pye Min took control of the Toungoo Empire from his brother Pindale Min and crowned himself king. Sensing the unrest in the Toungoo Empire and a renewed opportunity to take control of Lan Na, King Narai prepared his armies and marched them north in December 1662.[5] Expecting an attack, the ruler of Lan Na sent a request to the Toungoo for military assistance.[6]

Ultimately King Narai and two Siamese armies invaded Lan Na and captured Chiang Mai in February 1663 before support from the Toungoo Empire was able to arrive. When the Burmese army did arrive they were caught in a trap, routed, and forced to return to Ava. King Narai quickly established the administrative rules for Lan Na as a suzerain of Siam, gathered the war booty, and returned home. Although, King Narai ordered his military to remain in Chiang Mai and enforce the administration of the country, he did very little else to maintain the ascendancy of Siam in Lan Na.[7][8]

Meanwhile in the Tenasserim coastal region, the Burmese were arresting and threatening to execute the Mons who had been conscripted to help defend against the Chinese invasion but failed to report for duty. Threatened with death, the Mons rebelled against the Burmese authorities and burned down Martaban.[9][10] In response, the Toungoo sent armed forces to put down the revolt. Afraid of retribution, many of the Mon fled into Siam seeking asylum. King Narai ordered Mon nobles in Siam to welcome and receive the refugees.[11]

In Burma, the King in Ava suspected that the Siamese were the instigators of the Mon unrest and ordered that a second army proceed to Martaban, put down the rebellion, advance into Siam if necessary and forcibly apprehend the Mon rebels. As the Burmese army reached Martaban, the Siamese became aware of their plans and began to prepare for battle. The Burmese entered Siam at Three Pagodas Pass and advanced over 100 km into Siam to Sai Yok. As the Burmese moved down the Khwae Yai River valley, the Siamese slowly surrounded the invaders. Ultimately King Narai’s armies attacked the Burmese from both the front and the rear. The Burmese were routed and retreated leaving behind many arms and provisions. The Siamese pursued the retreating Burmese back to their own border and stopped, ending Burma’s 1663 invasion of Siam.[12][13][14]

Shortly thereafter in November 1663, partially in retaliation for the recent invasion and partially because he felt that he had a military advantage, King Narai and the Siamese launched a three-pronged invasion of Burma. The army stationed in Lan Na marched west with the objective to enter Burma at Papun. The Siamese army of the northern provinces marched west via Mae Lameo with the objective to enter Burma and attack Martaban. And a third Siamese army marched northwest via Three Pagodas with the objective to capture Tavoy and then advance on Martaban and Moulmein.[15]

Beyond the fact that Siam invaded Burma, there is disagreement regarding the ultimate territory invaded and the outcome of the campaign. The Burmese acknowledge that the Siamese attacked Martaban and Tavoy, but claim that they defeated the invaders and forced them to retreat home. The Siamese claim that they marched as far north as Ava, invested the capital city, but then returned home when their provisions were exhausted.[16] Among other authors and historians there is some support that the Siamese penetrated southern Burma and captured Rangoon.[17][18]

Thai statesman, historian, and author, Prince Damrong Rajanubhab examined the campaign histories of both Burma and Siam along with the account of the Mon. In his analysis, Rajanubhab recognized that a campaign all the way to Ava would be quite arduous because of the distance. Regardless, Rajanubhab insists that the Siamese narrative of the campaign is quite detailed and difficult to ignore. Rajanubhab also points out that the Mon narrative supports the Siamese history with the exception that the Mon claim the invasion force attained and invested Bagan, the capital city of the old Bagan Kingdom. Rajanubhab makes the argument that a campaign to Bagan would have been possible whereas a campaign to Ava would have been impossible.[19] It is interesting to note that although Ava is farther north, Bagan is farther west and the distance from Martaban to Bagan (711 kilometers) is actually greater than the distance from Martaban to Ava (693 kilometers.)[20]

For the record, Rajanubhab claims the Siamese invasion force overwhelmed the Burmese with their numerical superiority and easily completed their initial objectives then moved on to capture the cities of Chittagong, Syriam, Rangoon, Hongsawadi, and Prome. Beyond those cities Rajanubhab believes that the Siamese continued their advance north and were ultimately stopped at the fortified city of Bagan. In this account, Bagan was invested by the Siamese with the battle waging back and forth until May 1664 when provisions became scarce and the Siamese retreated home prior to the rainy season. In this account, both forces were decimated and the Burmese allowed King Narai’s armies to retreat back to Siam without pursuit.[21]

The only point of agreement between Rajanubhab's Siamese account and the Burmese account is that the invaders depleted their provisions during the invasion and had to return home.[16]