Nanthasen (also spelled Nanthasan; lo, ພຣະເຈົ້ານັນທະເສນ, died 1795), also known as Chao Nan, was the 6th king of the

Kingdom of Vientiane Kingdom of Vientiane was formed in 1707 as a result of the split of the Kingdom of Lan Xang. The kingdom was a Burmese vassal from 1765 to 1824. It then became a Siamese vassal until 1828 when it was annexed by Siam. History In 1779, under ...

. He ruled from 1781 to 1795. Nanthasen was the eldest son of his father

Ong Bun Phrachao Siribounyasan ( lo, ພຣະເຈົ້າສິຣິບຸນຍະສາຣ; th, พระเจ้าสิริบุญสาร; died November 1781), also known as Ong Boun (), Bunsan or Xaiya Setthathirath III, was the 3rd king ...

. In 1778, King

Taksin King Taksin the Great ( th, สมเด็จพระเจ้าตากสินมหาราช, , ) or the King of Thonburi ( th, สมเด็จพระเจ้ากรุงธนบุรี, ; ; Teochew dialect, Teochew: Dên ...

Siam Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Mainland Southeast Asia, Indochinese Peninsula, spanning , with a population of almost 70 mi ...

decided to invade three Lao kingdoms because they were pro-Burmese, and the Burmese King considered the Lao kingdoms as his base to expand further east. A Siamese army under Somdej Chao Phya Mahakasatsuek (later

Rama I Phra Phutthayotfa Chulalok Maharaj (, 20 March 1737 – 7 September 1809), personal name Thongduang (), also known as Rama I, was the founder of the Rattanakosin Kingdom and the first monarch of the reigning Chakri dynasty of Siam (now Tha ...

) invaded Vientiane. Nanthasen was appointed the commander-in-chief to fight against Siam. The Kingdom of Vientiane was defeated, and Ong Bun fled into the jungle. Nanthasen was captured by the Siamese army and taken to

Thonburi __NOTOC__ Thonburi ( th, ธนบุรี) is an area of modern Bangkok. During the era of the Kingdom of Ayutthaya, its location on the right (west) bank at the mouth of the Chao Phraya River had made it an important garrison town, which is ...

together with his brothers. The

Emerald Buddha The Emerald Buddha ( th, พระแก้วมรกต , or ) is an image of the meditating Gautama Buddha seated in a meditative posture, made of a semi-precious green stone (jasper rather than emerald or jade), clothed in gold. and about ...

and

Phra Bang The Phra Bang ("Royal Buddha Image in the Dispelling Fear mudra"), Lao ( ພະ + ບາງ) is the palladium of Laos. The Lao-language name for the image has been transliterated in a number of ways, including "Pra Bang," "Prabang," "Phabang" and ...

were also taken to Thonburi. Vientiane became Siam dependency.Wyatt, p. 143 In 1781, Nanthasen was allowed to return to Vientiane as king. The Phra Bang was also returned to Vientiane. However, his younger brother

Inthavong Chao Inthavong ( lo, ເຈົ້າອິນທະວົງສ໌; th, เจ้าอินทวงศ์; died 7 February 1805), or known as his regnal name Xaiya Setthathirath III, was the 5th king of the Kingdom of Vientiane (r. 1795 to 1805 ...

was crowned the ''

oupahat Uparaja or Ouparath, also Ouparaja ( my, ဥပရာဇာ ; km, ឧបរាជ, ; th, อุปราช, ; lo, ອຸປຮາດ, ''Oupahat''), was a royal title reserved for the viceroy in the Buddhist dynasties in Burma, Cambodia, and ...

'' ("vice king") by Siam, and left in

Bangkok Bangkok, officially known in Thai language, Thai as Krung Thep Maha Nakhon and colloquially as Krung Thep, is the capital and most populous city of Thailand. The city occupies in the Chao Phraya River delta in central Thailand and has an estima ...

as hostage. During Nanthasen's reign, Vientiane also invaded

Muang Phuan Meuang Phuan ( Lao: ເມືອງພວນ; Country of Phuan) or Xieng Khouang (Lao: ຊຽງຂວາງ), also known historically to the Vietnamese as Trấn Ninh ( Hán Việt: 鎮寧; lit. "securement of peace"), was a historical principal ...

, and captured its capital Xieng Khouang. In 1791, Nanthasen convinced Rama I that King

Anurutha Chao Anurutha (also spelled Anouruttha or Anurathurat; lo, ເຈົ້າອານຸຣຸດທະ; 1737 – 31 December 1819) was the king of Luang Phrabang from 1792 to 1819. Anurutha was the fourth son of king Inthasom. He was appointed the ...

Luang Prabang Luang Phabang, ( Lao: ຫລວງພະບາງ/ ຫຼວງພະບາງ) or ''Louangphabang'' (pronounced ), commonly transliterated into Western languages from the pre-1975 Lao spelling ຫຼວງພຣະບາງ (ຣ = silent r) ...

was secretly meeting with the Burmese and plotting a rebellion against Siam. He was permitted to attack

, and captured the city in 1792. After the

Battle of Ngọc Hồi-Đống Đa The Battle of Ngọc Hồi-Đống Đa ( vi, Trận Ngọc Hồi - Đống Đa; ), also known as Victory of Kỷ Dậu ( vi, Chiến thắng Kỷ Dậu), was fought between the forces of the Vietnamese Tây Sơn dynasty and the Qing dynasty in ...

, a Vietnamese

Lê Le is a romanization of several rare East Asian surnames and a common Vietnamese surname. It is a fairly common surname in the United States, ranked 975th during the 1990 census and 368th during the 2000 census. In 2000, it was the eighth-most-co ...

prince,

Lê Duy Chỉ Le is a romanization of several rare East Asian surnames and a common Vietnamese surname. It is a fairly common surname in the United States, ranked 975th during the 1990 census and 368th during the 2000 census. In 2000, it was the eighth-most-co ...

(黎維祗), fled to

Tuyên Quang Tuyên Quang () is a city in Vietnam, and is the capital of Tuyên Quang Province. History The French post at Tuyên Quang was defended for four months against 12,000 troops of the Yunnan Army and the Black Flag Army by two companies of the Fre ...

and

Cao Bằng Cao Bằng () is a city in northern Vietnam. It is the capital and largest settlement of Cao Bằng Province. It is located on the bank of the Bằng Giang river, and is around away from the border with China's Guangxi region. According to the 2 ...

, to fight against

Tây Sơn dynasty The Tây Sơn dynasty (, vi, Nhà Tây Sơn (Chữ Nôm: 茹西山); vi, Tây Sơn triều ( Hán tự: 西山朝) was a ruling dynasty of Vietnam, founded in the wake of a rebellion against both the Nguyễn lords and the Trịnh lords befor ...

. Chỉ devised a plan to unite Vientiane and

in a revolt of Tây Sơn dynasty. In 1791, Vientiane was invaded by Tây Sơn dynasty, Nanthasen had to flee. Finally, he reached an accommodation with Tây Sơn dynasty. In January 1795, Nanthasen accused of plotting a rebellion'' Đại Nam chính biên liệt truyện sơ tập''
vol. 32
/ref> with the Lao governor of

Nakhon Phanom Nakhon Phanom ( th, นครพนม, ) is a town (''thesaban mueang'') in northeastern Thailand, capital of Nakhon Phanom Province. The town covers ''tambons'' Nai Mueang and Nong Saeng and parts of ''tambons'' At Samat and Nong Yat, all in M ...

, allegedly having made diplomatic overtures to Tây Sơn. He was deposed and taken to Bangkok as a prisoner. He died there in June or July 1795, childless. His younger brother

succeeded.

References

* *
Siamese/Thai history and culture–Part 4
Kings of Vientiane 1795 deaths 18th century in Vientiane 18th-century monarchs in Asia 18th-century Laotian people {{Laos-royal-stub