The Siamese under King Rama I and his younger brother Prince Maha Sura Singhanat successfully warded off Burmese invasions.

King Bodawpaya sent his son Prince Thado Minsaw to concentrate his forces on Kanchanaburi in only a single direction to invade Siam.

Traditional rivalries and dispute over Mon rebels and the Tenasserim coast led to the Burmese-Siamese wars in the eighteenth century.

After waiting for four days at Martaban, King Bodawpaya was furious that the transportation of men, horses and elephants across the Salween River was delayed and had not been completed.

[5] The captured Burmese revealed to Siamese authorities that King Bodawpaya was planning a massive invasion of Siam in multiple directions.

Due to a lack of supplies, Bodawpaya couldn't commit all his forces, numbering 88,000 men, present at the Kanchanaburi front.

Prince Maha Sura Singhanat with 30,000 men marched from Bangkok in December 1785 along with his generals and retinue, reaching Lat Ya (Thai: ลาดหญ้า) (called Kanpuri in Burmese) in Kanchanaburi.

He sent the Mon general Phraya Mahayotha or Binnya Sein to intercept the Burmese at Kram Chang (in modern Si Sawat District).

Minhla Kyawdin and Mingyi Maha Mingaung the Burmese generals, unable to withstand Siamese attacks anymore, retreat.

Nemyo Nawrahta himself led an army of 4,000 men through the Bong Ti Pass (in modern Sai Yok District, Kanchanaburi Province) and stationed at Chom Bueng.

Nemyo Nawrahta also sent his subordinate Dawei Wun to lead an army of 3,000 men to enter Ratchaburi through Suan Phueng.

Chao Phraya Thamma Boonrot, who led the Siamese army of 5,000 men in Ratchaburi town, was still unaware of these Burmese advances.

Nemyo Nawrahta at Chom Bueng, upon seeing the defeat of Dawei Wun at Khao Ngu, also decided to retreat as soon as he had received orders from King Bodawpaya.

Prince Maha Sura Singhanat was angry that the Siamese general Chao Phraya Thamma Boonrot had allowed the Burmese to penetrate so deep into Ratchaburi.

Prince Thado Thiri Maha Uzana also sent his Sitke, Nemyo Sithu, to lead an army of 3,000 from Lampang down south towards the Upper Chao Phraya Plains.

The governors of Sawankhalok, Sukhothai and Phitsanulok, due to manpower shortages, decided to abandon their cities and flee into the jungles as they were unable to raise armies against the Burmese.

The Siamese army of Prince Anurak Devesh in Upper Chao Phraya Plains was at risk of being attacked from two directions; from Pakphing by Nemyo Sithu in the north and from Tak by Nawrahta Kyawgaung from the west.

Prince Anurak Devesh ordered Phraya Phraklang Hon to stay at Chai Nat to defend the rear lines against possible Burmese attacks from Tak.

King Rama I sent message to his nephew Prince Anurak Devesh at Nakhon Sawan, urging him to initiate the attacks against the Burmese.

King Rama I ordered another nephew Prince Thepharirak and Phraklang Hon at Chai Nat to march against Nawrahta Kyawgaung at Tak.

When Prince Thepharirak sent Phraklang Hon had reached Kamphaeng Phet, however, Nawrahta Kyawgaung at Tak retreated after the Burmese defeat at Pakping and the engagements did not occur.

The Burmese general Maha Thiri Thihathu ("Kinwun Mingyi" in Thai sources) sailed the massive fleet of 10,000 men from Mergui to the Siamese Andaman Coast in December 1785.

As Thalang was left with no governor, Chan and her sister Lady Muk, together with her son Thien and her cousin Thongpun the vice-governor, organized the local defense against the Burmese invasion.

Maha Thiri Thihathu sailed his 7,000-men fleet to disembark at Ranong, continuing to Kraburi and crossing the Tenasserim Hills at Pakchan to attack Chumphon.

The governors of Chumphon and Chaiya decided to abandon their towns in the face of Burmese invasion due to manpower shortage.

Maha Thiri Thihathu and Nemyo Gonnarat sacked both towns and continued southward to Nakhon Si Thammarat (Ligor).

Maha Thiri Thihathu, however, had a Siamese man from Chaiya to yell at the Ligorian army that Bangkok had already fallen to the Burmese.

Maha Thiri Thihathu took Nakhon Si Thammarat with ease, plundering the city and enslaving the native Siamese.

Prince Maha Sura Singhanat ordered Chao Phraya Nakhon Phat to be brought to him for the crime of cowardice.

King Bodawpaya sent his son Prince Thado Minsaw to concentrate his forces on Kanchanaburi in only a single direction to invade Siam.