With that name, they historically identified themselves as the inhabitants of the alluvial plains, river valleys and plateaus of their native area, where they lived in local communities, called muang, and cultivated rice on paddy fields.

That distinguished them from the indigenous peoples of the area ("hill tribes"), like the Lua', who lived in the wooded mountains practicing slash-and-burn agriculture.

At the same time, it was a term of dissociation from the Burmese and Siamese, who held suzerainty over the Lanna Kingdom for centuries and who were not "people of our muang".

[6] The exonym Tai Yuan is likely derived from Sanskrit yavana meaning "stranger," which itself comes from the name of the Greek tribe of the Ionians, or from Pali yonaka.

[18][19] < According to linguistic and other historical evidence, Tai-speaking tribes migrated southwestward to the modern territories of Laos and Thailand from Guangxi sometime between the 8th and the 10th centuries.

[20] The Tai assimilated or pushed out indigenous Austroasiatic Mon–Khmer peoples, and settled on the fringes of the Indianized kingdoms of the Mon and Khmer Empire.

The core of their original settlement area lies in the basin of the Kok and Ing rivers in what is now Chiang Rai province.

Since the Yuan, like other Tai peoples, traditionally live from wet rice cultivation, they settled only in the river plains of northern Thailand, not in the mountain ranges that run through it and make up three quarters of the area.

In the 8th century, the city of Yonok was founded in the area of today's Chiang Saen district by subjugating the pre-existing Khmu and Lawa populations.

Around the year 850, the seventh king of Hiran, Laokiang, had Yonok rebuilt on the current site of Chiang Saen, which took the name of Ngoenyang and became the new capital.

Mangrai, the ruler of Mueang Ngoenyang, united a number of these principalities after his accession to the throne around 1259 and founded the city of Chiang Rai in 1263.

Around 1292 he conquered the Mon kingdom of Hariphunchai, which had dominated large parts of what is now northern Thailand in political, economic and cultural terms.

That laid the foundation for the new Kingdom of Lan Na ("One Million Rice Fields") when its capital, Mangrai, founded Chiang Mai in 1296.

The remaining Mueang, which were dependent on Lan Na, retained their own dynasties and extensive autonomy, but had to swear loyalty to the king and pay tribute (mandala model).

Lan Na was ethnically very heterogeneous and the Northern Thai did not constitute the majority of the population in large parts of their domain.

[31] At the same time, however, Ayutthaya was expanding north and Siamese troops penetrated deep into the Yuan-inhabited area of Lan Na.

As there was often a shortage of labour in pre-modern Southeast Asia, it was customary after wars to drag parts of the population of the defeated party to the area of the victor.

In the 17th century, after the subjugation of Lan Na by the Burmese, some Tai Yuan were brought to their capital Ava, where they belonged to the category of royal servants and provided lacquerware.

[36] The Siamese King Rama V (Chulalongkorn) wrote in 1883 to his high commissioner in Chiang Mai about the Tai Yuan, which he called "Lao":[37] We consider Chiang Mai as still not belonging to the Kingdom proper because it still is a prathetsarat (i. e. tributary state), but we do not plan to destroy the (ruling) families and to abandon prathetsarat (status).

The effects of Thaification in the wake of Monthon reforms have caused few northern Thai to be able to read or write it, as it no longer represents accurately the orthography of the spoken form.

Since then, some Northern Thai women, mainly the middle and upper classes, have been wearing the classic dresses of the north again on special occasions, made of hand-made cotton.

Chiang Mai is historically one of the places where Lanna sacred art has developed the most, with ancient temples and Buddha sculptures.

In Laos, religious practices have returned to normal after the obstacles posed by the communist government in the first years after the seizure of power in 1975.

The second legend reports that Chao Luang Kham Daeng is the lord of the ogres who guard the treasure of the sacred cave of Chiang Dao.