Anglo - Siamese war (1687)
In 1684, a British East India Company factory was forced to close as the foreign policy of Siam, directed by a Greek adventurer named Phaulkon, swung to the favor of the French. England was slow to act. In 1686, a royal proclamation withdrew the right of Englishmen to serve on foreign ships, and to implement it and press for payment of damages for the factory, two English ships, were sent to Siam.
They arrived shortly after a French fleet had been sent scurrying. Overnight shelling sank one English ship, killed sailors ashore, and forced the second to flee. Although war was declared soon after, it was not pursued. In 1688, an anti-foreign coup toppled Phaulkon, and Siam closed its ports to all foreigners for 150 years.
Siamese - Cambodian War of 1714 - 1717
In 1714, a civil war of succession, saw the new Cambodian king, Prea Srey Thomea over thrown by his uncle Keo Fa who had been the former king and had help from a Vietnamese army and some Laotian troops in regaining the throne. The ousted king promptly fled to Siam where he requested aid from King Bhumindaraja (Phra Chao Thai Sa), who wanted to offset increasing Vietnamese power in Cambodia. But his attempts to restore Prea Srey Thomea as rightful king failed in 1715 and in 1716.
In 1717, Bhumindaraja sent two large expeditionary forces into Cambodia, the larger via Siemreab in the north, the other with naval support along the gulf of Siam. At the battle of Banteay Meas, the southern force was crushed by a combined Cambodian and Vietnamese force because the Siamese fleet panicked under attack, took to sea, and was ruined in a storm.
The northern Siamese forces, however, were victorious, advancing to the Cambodian capital of Udong. There in return for his surrender and allegiance to Siam, Keo Fa was allowed to keep his throne; Prea Srey Thomaes cause was given up.
Siamese Civil war of 1733
In 1733, the death of King Bhumindaraja, saw a fierce struggle between his second son, Prince Aphai and King Bhumindarajas younger brother Boromokot, who had the imperial rank of heir apparent; earlier Bhumindaraja tried to change the royal succession from his brother to Aphai.
At first the Princes forces seemed superior, but as Boromokots troops pushed towards the Thai Grand Palace, Aphais troops deserted him, allowing Boromokot to become king and take control of the capital Ayutthaya. The fleeing Aphai and a brother were soon captured in a swamp and killed; Boromokot ruthlessly slaughtered all of his major enemies. After suppressing an attack on the Palace by 300 rebel Chinese in 1733, the king reigned peacefully until his death.
Siamese - Burmese War of 1764 - 1769 (Phya Taksin)
In 1764, Burmese King Hsinbyushin of the Konbaung dynasty, pursued a policy of expansionism at the expense of neighboring countries. His troops invaded Siam, seizing the Chiengmai area before marching on to invade Laotian territory.
he successful campaign then moved south to the capital Ayutthaya, which was besieged and captured in April 1767, thanks mainly to the skillful Burmese General Maha Nawraha, who died shortly before victory. The city was sacked; General Maha Nawrahas troops ran amok once inside the city and many of its rich artistic treasures were destroyed or taken. Afterwards the Burmese Capital was moved south to Thon Buri and then Bangkok. Thousands of captives were taken as slaves to Burma. Siamese General Phya Taksin began to recruit an new army.
During the recruitment of Siamese troops, Phraya Pichai a soldier and champion fighter from Uttarradit became General Taksins aid-de-campe, here they formed a small army of 500 men and began guerrilla warfare against the Burmese, retaking town after town on their march to liberate the city of Bangkok.
In 1768, General Taksin, finally arrived on the capital of Bangkok and in the ensuing battle against Burmese King Hsinbyushin troops, was victorious. Taksin, having assumed the Siamese throne in 1767, confronted and defeated two rivals for the crown in 1769, subsequently unifying the country again.
In 1770, when the a Vietnamese attacked the Siamese towns of Trat and Chanthaburi, Taksin launched a land and sea invasion of Cambodia, seizing Banteay Meas, Phnom Penh and other places. As the Siamese advanced on the capital at Banteay Pech, the Vietnamese- backed puppet ruler fled, and Ang Non was restored on the throne as a vassal of Siam. But Vietnam again intervened: one force occupied Rach Gia on the gulf of Siam; another sailed up the Mekong River to Phnom Penh, won a battle there, and restored the Ang Nons brother back on the throne.
By 1773, however, the Vietnamese had suffered defeat, and in 1775 Ang Non, once again was placed on the throne. He managed to check another attack on him by the Vietnamese the following year.
Siamese - Vietnamese war of 1769 - 1773
1759, Cambodias eastern provinces had been falling under Vietnamese control and in the the same year, Cambodias King Ang Non (died 1779) was deposed by his brother, who relieved help from Vietnam and afterward refused to pay tribute to Siam. King Taksin marched east and occupied the Cambodian areas of Siemreab and Battambang.
Siamese - Burmese war of 1775 - 1776
In 1769, King Taksin made an unsuccessful military attempt to regain control of Chiengmai which had been seized by King Hsinbyushins Burmese troops.
In 1775, six years later King Taksins invading troops were triumphant; an effort by King Hsinbyushin to retake Chiengmai failed the following year. Vietnams Emperor Gia Long (1762-1820) sent a large force whose intimidating presence in Cambodia caused the Siamese to withdraw without fighting Ang Chan was enthroned again.