Pai, Thailand

The recorded history of the area starts about 800 years ago, with the establishment of a settlement (today known as Ban Wiang Nuea) about 3 km north of modern-day Pai. Ban Wiang Nuea was founded in 1251 CE by Shan immigrants from the region of modern-day northern Myanmar. Due to the area's remoteness and seclusion, people in those times were mostly cut off from news of the outside world and therefore not much concerned with the politics of Lanna and the rest of Thailand. That changed drastically during the course of the 14th and 15th centuries, when the first settlers arrived from Chiang Mai. It was part of Lanna policy at the time to send citizens loyal to the throne to the outposts of the empire, in order to consolidate and affirm its territorial authority. The result was a conflict that eventually led to a series of wars over territorial dominance in the Pai area. Lanna troops finally defeated the Shan in 1481, forcing them to retire to Burmese territory. The Shan families who had lived in the area for a long time, establishing households, farming land, and raising families, were granted permission to stay by the Lanna prince, along with a certain degree of cultural and social autonomy under the law and authority of the Lanna kingdom. Ban Wiang Nuea as a result became a village strictly divided by a wall into a Shan part and a Lanna part.

In the second half of the 19th century, colonial powers France and England, who had already established their influence in Vietnam, Cambodia, Laos, and Burma, were viewing the area of modern-day Thailand with increasing interest. To consolidate Siam's influence and authority in the northern border region, the royal house encouraged northern Thais from provinces such as Phayao, Lamphun, and Nan to migrate to those areas. The result again was conflict: the last fight between Lanna and the Shan in Ban Wiang Nuea took place in 1869, when Lanna soldiers defeated their Shan opponents in a battle that ended with the total destruction of the village, which was burnt to the ground. All structures standing in Ban Vieng Nuea today are the result of the subsequent rebuilding efforts of the villagers.

There was already a road (that took up to a week to traverse) leading from Chiang Mai to Pai in the late 19th century. The settlement, then known as Ban Wiang Tai, developed into the modern town of Pai. Many new immigrants chose to settle in the area along the connecting network of trails to Mae Hong Son.

In 1943, Japan began several projects to create efficient troop and equipment transport routes between Thailand and Myanmar in support of their planned attacks on Imphal and Kohima. In addition to the so-called Death Railway through Kanchanaburi, this included improvement of the existing road from Chiang Mai to Pai as well as the patchwork of trails leading north to Mae Hong Son. A bridge spanning the Pai River about 10 km southeast of the city was built after the war and erroneously named the "World War II Memorial Bridge". It was apparently erected (and subsequently twice extended) in the course of road improvement projects by the Thai government. The Japanese efforts to develop road networks were abandoned in early 1944, when it became evident that the improvements could not be completed in time for the scheduled attack on Imphal. The incomplete road did serve as an avenue of retreat for the Japanese after their disastrous defeat at Imphal and Kohima, however.

In 1967, the Thai government started developing the road leading from Chiang Mai via Pai to Mae Hong Son, known today as Route 1095, but didn't finish paving it until the early- to mid-1990s.

In addition to the waves of old Shan and Lanna immigrants, Karen migrants arrived in the 18th century, Lisu and Lahu people from areas of southern China came in the early 20th, Muslim families from Chiang Mai began arriving to establish trading businesses starting around 1950, a group of Kuomintang soldiers fleeing China in the wake of their defeat in the Chinese Civil War established a community in Pai in the early 1960s, and finally, a new wave of refugees from the Shan State of Burma have migrated to the area in the past few decades, fleeing the turmoil in Myanmar to work as laborers in Thailand.

Pai suffered a huge mudslide and severe flooding in 2005, resulting in major structural damage to homes, resorts, storefronts, and bridges.