Chaophraya Aphaiphubet (Baen)

Chaophraya Aphaiphubet (Baen) (,?–November 1809), also known as Chauvea Tolaha Ben or Chaofa Talaha (Baen) or Chau Hua Pen , was the Regent of Cambodia during the minority of the Cambodian king Ang Eng under Siam's influences and eventually became the first of the line of Siam-appointed governors of Battambang or Phra Tabong. He was known in Vietnamese texts as Chiêu Thùy Biện (昭錘卞). He is officially regarded as the founder of House of Abhaiwongse.

Serving King Ang Non Baen was a Cambodian noble with the title Oknya Yomreach (, Thai counterpart of this title was Phraya Yommarat ). Oknya Yomreach Pen or Baen was the Cambodian Minister of Justice in the reign of the pro-Siamese Cambodian king Ang Non. According to Battambang Samay Lok Mchas or "Battambang during the time of Lord Governor" by Tauch Chhoung, published in 1974, Baen originated from Treang in modern Takeo Province. Baen served Prince Ang Non. He probably accompanied Ang Non during political flight from Cambodia to Ayutthaya in 1758 and followed King Ang Non, who, in turn, followed Phraya Tak the Chinese–Siamese mandarin, breaking through the Burmese siege out of Ayutthaya in 1767. Phraya Tak later became King Taksin of the Siamese Thonburi kingdom.

Siamese Invasion of Cambodia: 1771–1773

King Taksin sent Siamese forces under Phraya Yommarat Thongduang (Rama I) to invade Cambodia in 1771 to bring Ang Non, the pro-Siamese contender, to the Cambodian throne. The incumbent pro-Vietnamese Cambodian king Ang Ton fled to Saigon, requesting aid from the Nguyen Lord of Cochinchina Nguyễn Phúc Thuần, who sent Vietnamese forces to repel the Siamese and restore Ang Ton in 1772. When the Siamese retreated from Cambodia in 1773, Ang Non and presumably Baen took position at Kampot in Southwestern Cambodia in resistance against Ang Ton.

In 1771, the three Tây Sơn brothers arose against the Nguyen Lord regime, killing the Nguyen Lord Nguyễn Phúc Thuần in 1777. made his own bid for power by bringing in Vietnamese armies under Đỗ Thanh Nhơn to seize power in Oudong the Cambodian royal capital, murdering all four sons of Ang Non and placing the seven-year-old king Ang Eng to invade Cambodia in three directions into Siemreap, Battambang and Kampong Svay in December 1781, intending to punish Tolaha Mou and to install his own son Prince Inthraphithak as the King of Cambodia. Chaophraya Chakri Thongduang and Chaophraya Surasi led Siamese armies to invade Cambodia, taking commanding position at Siemreap. Baen was assigned to lead a Cambodian regiment under Siam to support Prince Inthraphithak as vanguard to attack Oudong, the Cambodian royal capital.

Chauvea Tolaha Mou took defensive position at Kampong Luong just north of Oudong, while Oknha Kralahom Sous led Cambodian riparian fleet into Tonle Sap to defend against the invading Siamese. Nguyễn Phúc Ánh the Nguyen Lord of Cochinchina to send Vietnamese armies under the Nguyễn Hữu Thụy to counter this Siamese invasion of Cambodia. Yomreach Baen, serving under Siam, led the army of Prince Inthraphithak, son of King Taksin, marching from Siemreap all the way through Battambang and Baribour, approaching Oudong. Nguyễn Hữu Thụy the Vietnamese commander took position at Chroy Changvar, commanding Oknha Yomreach Peang to defend against the Siamese at Kaoh Chen, opposite of Longvek on Tonle Sap River. Yomreach Baen's Cambodian–Siamese forces engaged with Cambodian–Vietnamese forces of Yomreach Peang at Peam Chumnik Political disruption at Thonburi compelled Chakri to halt his Cambodian campaign, reaching a truce with the Vietnamese and returned to Thonburi. This Siamese invasion of Cambodia was thus cut short by instability at home. When Chaophraya Chakri had taken control of Thonburi, in April 1782, Chaophraya Surasi commanded Baen to surround Prince Inthraphithak with his own Cambodian forces to keep Inthraphithak uninformed about events in Thonburi. Inthraphithak, unaware that his father King Taksin had been executed and the regime had changed, sent a complaint to Thonburi, saying that Baen had turned rebellious and his Cambodian men were surrounding him. Inthraphithak broke free from Baen's encirclement and realized the situation. Inthraphithak was eventually captured and executed at Thonburi.

Struggle in Cambodia

First attempt to seize power in Cambodia Chaophraya Chakri ascended as King Rama I in 1782, founding the Chakri dynasty. Baen had instrumental role in the ascension of the king. Formerly a Cambodian minister, Baen then became a loyal aide of the Siamese king. Meanwhile, in Cambodia, Oknha Kralahom Sous had declared himself Samdech Chauponhea or Second Chief Minister, second only to the Chauvea Tolaha himself. Uneasy pact between Chauvea Tolaha Mou and Samdech Chauponhea Sous began to crumble. Sous decided to get rid of Tolaha Mou altogether. Sous sent a secret letter to his 'sworn friend' Yomreach Baen at Bangkok, asking Baen to join him in Cambodia to overthrow the rule of Tolaha Mou.

Yomreach Baen told King Rama I of Siam about this secret letter from his friend in Cambodia. The Siamese king saw this as an opportunity to expand Siamese influence into Cambodia. King Rama allowed Baen to bring forces into Cambodia to seize power. Samdech Chauponhea Sous personally waited for Baen at Battambang as escorted Baen to Oudong, where they conspired to overthrow Tolaha Mou the Cambodian Prime Minister. Sous and Baen led forces to capture Tolaha Mou, who fled to Bassac (Ba Thắc, in modern Sóc Trăng province at the mouth Bassac River) but the Cambodian governor of Bassac arrested Tolaha Mou and sent him back to Oudong, where Tolaha Mou was executed in October 1782. Pact of these 'sworn friends' Sous and Baen in Cambodia lasted only for two months until Baen eventually murdered Sous in December 1782, taking all power to himself. Baen declared himself Chauvea Tolaha or Prime Minister of Cambodia, also allying with Oknha Kralahom Pok the caretaker of young king Ang Eng. The ten-year-old king Ang Eng had been a powerless puppet king since his ascension in 1779 while his powerful ministers vied for power in Cambodia.

Oknha Decho Ten, governor of Kampong Svay and brother of Tolaha Mou, was still standing against Baen at Kampong Svay. When Yomreach Baen sent his forces under Oknha Chakrey Kep to attack Kampong Svay, the Chams of Tbong Khmum, under leadership of a Cham official Tuan Set the Cambodian royal capital.

In Bangkok, King Rama I assigned a residence for the Cambodian king Ang Eng at Sanam Kraboe or Buffalo Meadows under his command to join this campaign. Baen was also assigned to bring his Cambodian forces from Battambang to join the main Siamese forces at Bassac (in modern Sóc Trăng province) to conquer Saigon. However, the campaign ended up with the Siamese defeat by the Tây Sơn in the Battle of Rạch Gầm-Xoài Mút urging both of them to cooperate.

In 1791, the Siamese king Rama I ordered Chaophraya Aphaiphubet Baen to bring 10,000 or Preah Noreay Reacheathireach

Though Tolaha Pok received this Vietnamese mission with pomp, the mission was diplomatically dangerous in regard to the opinion of Siam. This Vietnamese visit prompted in 1837. Lacking male candidates, Trương Minh Giảng sent a secret letter to Ang Em at Battambang, Execution of Princess Ang Pen and exile of other Cambodian princesses and Oknhas caused the Cambodians, who were dissatisfied with Vietnamese rule, to generally arose in 1840.

With Cambodia in general uprising against Vietnam, in November 1840, King Rama III sent Lao–Northern Khmer–Siamese multiethnic forces of 20,000 men under Bodindecha from Battambang to reclaim Cambodia. Death of the Vietnamese Emperor Minh Mạng in 1841 prompted the Vietnamese to retreat from Cambodia. Losing Cambodia, Trương Minh Giảng committed suicide. Chaophraya Bodindecha installed Ang Duong as Siam-backed candidate at Phnom Penh and sent Cambodian–Siamese forces under Chaophraya Yommarat Bunnak, joined by Preah Angkeo Ma (son of Chaophraya Aphaiphubet) and Ang Duong himself, to attack Southern Vietnam, leading to the Battle of Châu Đốc in April 1842, in which the Siamese suffered heavy defeat. Preah Angkeo Ma was killed in this battle along with nine other pro-Siamese Cambodian Oknhas and 1,200 soldiers.