The Lao are an ethnic group native to Laos and northeastern Thailand. The Lao are the majority group of Laos at 53. 2%. Today, significant Lao populations can be found in the United States, France, Cambodia, Canada, Myanmar, Thailand and they belong to the family of Tai-Kadai peoples. The etymology of the word Lao is uncertain, although it may be related to known as the Ai Lao who appear in Han Dynasty records in China. Tribes descended from the Ai Lao included the Tai tribes that migrated to Southeast Asia, according to Michel Ferlus, ethnonym and autonym of the Lao people, nationality of the inhabitants of Laos is formed by the monosyllabization of the Austroasiatic etymon for human being *k. raw. The peoples named Lao, supposed to be the ancestors of Lao and some other Tai-Kadai populations, settled in the upper Tonkin and in parts of Yúnnán and this reconstruction of the pronunciation for the phonogram 獠 confirms that ‘Lao’ originates in the etymon *k. raːw. The English word Laotian, used interchangeably with Lao in most contexts, in Laos, little distinction is made between the Lao and other closely related Tai peoples with mutually intelligible languages who are grouped together as Lao Loum or Lowland Lao. The possible reasons for Tai migration include pressures from Han Chinese expansion, Mongol invasions, suitable land for wet rice cultivation, the Tai assimilated or pushed out indigenonus Austroasiatic Mon–Khmer peoples, and settled on the fringes of the Indianised kingdoms of the Mon and Khmer Empire. The Tai states took advantage of the waning Khmer Empire and emerged independent, the Lao reckon the beginnings of their national history to this time, as many important monuments, temples, artwork, and other aspects of classical Lao culture harken back to this time period. From this point, one can refer to the Tai states of the Chao Phraya River valley as Siam and, albeit quite anachronistically, Lan Xang as Laos. The Kingdom of Lanxang, the Land of One Million Elephants, began in 1354 AD, the powerful Kingdom of Lan Xang had wealth and influence due to the location of its capital along the Silk Route and also serving as the center of Buddhism in Southeast Asia. Numerous temples, especially in Xieng Thong and Vientiane, attest this, during this time, the legends of Khun Borom were recorded on palm-leaf manuscripts and the Lao classical epic Sin Xay was composed. Therevada Buddhism was the religion, and Vientiane was an important city of Buddhist learning. Cultural influences, besides Buddhism, included the Mon outposts later assimilated into the kingdom, the libraries of Lannathai were copied, including much religious literature. This may have led to the adoption, or possibly re-adoption, of the Mon-based Tua Tham, the kingdom split into three rival factions, ruling from Luang Phra Bang, Vientiane, and Champasak. The kingdoms quickly fell under Siamese rule, during both these periods, Vientiane and other cities were looted and their Buddha images and artwork moved to Thailand. By the time the French reached Laos in 1868, they had found a depopulated region with even the great city of Vientiane disappearing into the forest. The area of Laos, then annexed by Siam, was explored by the French and, under Auguste Pavie, the French, as overlords of Vietnam, wanted all the tributaries of Vietnam, including the remnant territories of Lanxang
The French forced the Siamese to renounce their claims to Lao territory in 1893, thus signalling the genesis of the modern Lao state.
Offering of food to monks to make merit at a temple in Vientiane