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The Burmese Crown Prince's First Invasion, 1590: The Tha Khoi Stream
A few months after Naresuan came to the throne, King Nanda Bayin sent the Crown Prince Mingyi Swa at the head of an army to attack Ayutthaya. The Thai chronicles say this army was routed around the Tha Khoi stream in the Suphanburi area, while the Burmese chronicles place it somewhere else entirely. That makes this campaign a good example of how to read the two sides' sources side by side.
The ≈ sign marks an approximate location. Borders on the map are modern and shown for orientation only. Campaign routes are approximate lines drawn from the chronicles and modern studies, not the exact path taken. Dashed lines are enemy armies.
A new king
King Maha Thammaracha died in 1590 and Naresuan succeeded him. Studies that recalculate the dates consider that this probably fell around 1 July 1590. Naresuan appointed Ekathotsarot as his crown prince (uparat).
The Crown Prince's army marches
According to the Thai chronicles, the Crown Prince left Hanthawaddy in the twelfth lunar month of 1590, around November, with Phraya Phasim and Phraya Phukam (lord of Pagan) in his army. They entered by the Three Pagodas Pass and came on past Kanchanaburi. Ayutthaya received the news late, so Naresuan had to hurry out with an army to meet them.
The battle at the Tha Khoi stream
Naresuan drew up his army to meet the enemy at the Tha Khoi stream in the Suphanburi area. When the two sides clashed, the Hanthawaddy army broke and fled, and Phraya Phukam was killed in the fighting. The Thais gave chase and captured Phraya Phasim at Ban Chorakhe Sam Phan, but the Crown Prince escaped and made it home.
Chorakhe Sam Phan is still the name of a subdistrict in U Thong district, Suphanburi province, but it has not been confirmed that it matches the village in the chronicles in every respect. Some English-language encyclopedias call the place where this army was routed Ban Khoi, and state that Prince Damrong Rajanubhab dated the campaign to about eight months after Naresuan's accession.
The Burmese chronicles tell another story
The Burmese chronicles record that the Crown Prince led about 20,000 men and set out on 24 November 1590, but that he invaded from Lan Na in the north and suffered a crushing defeat outside Lampang in March 1591.
Although the places and routes differ widely, the sources of both sides agree on the essentials: the Crown Prince's army was heavily defeated, and when it returned King Nanda Bayin handed out punishments. The Burmese side says some senior commanders were executed; the Thai side says the Crown Prince was formally reprimanded.
After the war, the balance of power begins to shift
Accounts based on the Burmese chronicles go on to record that in the dry season of late 1591 to early 1592 Siam began to take the offensive, sending about 5,000 men to attack the upper Tenasserim coast. Although they were driven back, it was a sign that the balance of power was changing. The Crown Prince's next campaign would be the war of the elephant duel at Nong Sarai.
Reading the route on the map
The line on the map follows the route in the Thai chronicles: the Hanthawaddy army entered by the Three Pagodas Pass, passed Kanchanaburi and reached the Tha Khoi stream, then broke and fled towards Chorakhe Sam Phan. The Tha Khoi stream and Chorakhe Sam Phan are approximate positions. If you follow the Burmese chronicles instead, the route would run further north, through Lan Na.
Waypoints along the route
| Waypoint | Coordinates | Notes |
|---|---|---|
| 1. Three Pagodas Pass | 15.302, 98.402 | |
| 2. Kanchanaburi | 14.019, 99.531 | Approximate location. Uses the coordinates of the present-day town, which was moved here in the reign of King Rama III; the Ayutthaya-period town stood at a different spot. |
| 3. Tha Khoi stream (Suphanburi) | 14.600, 100.000 | Approximate location. The exact battle site is unknown. The encyclopedia says the Tha Khoi stream was near Nong Sarai, so the point is placed roughly in Don Chedi district. |
| 4. Ban Chorakhe Sam Phan (Phasim captured) | 14.376, 99.892 | Approximate location. Uses the coordinates of U Thong district, which contains Chorakhe Sam Phan subdistrict; not confirmed to match the village in the chronicles. |
Where historians still disagree
- Route and battlefield: the Thai chronicles say the army came in by the Three Pagodas Pass and was routed at the Tha Khoi stream in the Suphanburi area, while the Burmese chronicles say it came through Lan Na and was routed outside Lampang. There is still no conclusion on which is right, or whether they record different parts of the same events.
- Place names: the English-language encyclopedia uses the name Ban Khoi, while Thai sources use the Tha Khoi stream and Ban Chorakhe Sam Phan.
- Timing: the Thai chronicles say the army set out in the twelfth lunar month of 1590 and the Burmese say 24 November 1590, which agree. But the Thai side gives no clear date for the battle, while the Burmese say the defeat came in March 1591.
Frequently asked questions
Did the Burmese Crown Prince attack Ayutthaya before the elephant duel?
Yes. According to the Thai chronicles, Crown Prince Mingyi Swa first invaded in late 1590 and was defeated at the Tha Khoi stream in the Suphanburi area, before coming back once more in the campaign of the elephant duel.
Why do the Thai and Burmese sources name different places?
The chronicles of both sides were compiled long after the events, each from its own point of view, so details such as place names can be inaccurate. Readers should compare several sources before drawing conclusions.
Last updated 10 November 2026