Isan: the Northeast

The plateau has one of Southeast Asia's most important prehistoric sites. At Ban Chiang in Udon Thani, excavations from the 1960s and 1970s found burials with red-painted pottery and bronze tools that showed people here were farming rice and working metal in prehistoric times, and prehistoric painters left images on the Mekong cliffs at Pha Taem.

From about the 10th to the 13th century the southern half of Isan was part of the Khmer empire. Roads linked Angkor to Phimai, whose temple buildings date largely from the late 11th to the late 12th century, and to Phanom Rung and dozens of smaller sanctuaries across Buri Ram, Surin and Si Sa Ket. The north looked instead to the Lao kingdom of Lan Xang, and Lao settlers spread across the plateau over the following centuries.

Siam brought the Lao lands under its control in the late 18th century and put down the rising of King Anouvong of Vientiane in 1826–28; in Nakhon Ratchasima, Thao Suranari is honoured for her part in resisting his army. Treaties with France in 1893 and 1904 made the Mekong most of the border and cut Isan off from the Lao capital. In the Cold War the United States flew from bases at Udon Thani, Ubon, Nakhon Phanom and Korat, while communist guerrillas were active across the region. Since the 2000s Isan has been a stronghold of support for Thaksin Shinawatra and the Red Shirt movement.

Most people in Isan speak Isan, a form of Lao, at home, though they write in Thai and use standard Thai in school and business. In the south, around Surin, Buri Ram and Si Sa Ket, many speak Northern Khmer, and the Kui people of Surin have long caught and trained elephants. The Mekong towns have Vietnamese communities, many descended from refugees.

The region's music is mor lam, sung verse accompanied by the khaen, a bamboo mouth organ, now played in a fast electric form at temple fairs and on the radio across Thailand, alongside luk thung country music, which draws many of its singers from Isan. Isan is also the home of the Thai forest monk tradition: Ajahn Mun and Ajahn Chah, whose monastery Wat Nong Pah Pong is near Ubon, drew disciples from around the world.

Festivals are loud and communal. Yasothon's Bun Bang Fai in May launches home- made rockets to call the rain; Ubon parades giant carved wax candles at the start of Buddhist Lent; Dan Sai in Loei holds Phi Ta Khon, with masked ghost dancers; and Surin stages its elephant round-up in November. Weaving matters too: mat mi, silk and cotton tie-dyed before weaving, is made in villages such as Chonnabot near Khon Kaen.

Isan has about 22 million people, around a third of Thailand's population, but few large cities. Nakhon Ratchasima, known as Korat, is the gateway; Khon Kaen, with its big university and hospitals, is the regional centre; and Udon Thani and Ubon Ratchathani are the other main cities, each with an urban area of roughly 400,000 people.

Most of the land is farmed, on thin, sandy soils that depend on the rains. Rice, including fragrant hom mali rice from the Thung Kula Ronghai plain, is the main crop, with cassava and sugar cane on drier land and rubber increasingly in the north. Incomes are the lowest in the country, and for decades Isan families have sent young people to work in Bangkok, the eastern factories and abroad, leaving grandparents to raise children in the villages. Remittances, and in places marriages to foreign men, have built many new village houses.

Village life turns on the temple and the rice calendar, with planting in the rains and harvest in November and December. Current issues include drought, debt, an ageing rural population, and a strong regional political identity.

Isan food, now eaten across Thailand, is sour, salty, fiery and herbal, and it is always eaten with khao niao, sticky rice, taken from a woven basket and rolled by hand. Som tam, green papaya salad pounded in a mortar with chilli, lime and fish sauce, comes in many versions, the strongest made with pla ra, a pungent fermented fish sauce that underpins much Isan cooking. Larb, minced meat or fish tossed with lime, chilli, mint and roasted ground rice, and nam tok, a similar salad of sliced grilled beef or pork, are the other staples.

Gai yang, chicken grilled over charcoal, is sold at every roadside, and sai krok Isan is a sour fermented pork-and-rice sausage. Soups include tom saep, a hot and sour broth, while insects — crickets, silkworm pupae and red ant eggs — are a seasonal snack. Korat gives its name to pad mi Korat, stir-fried rice noodles, and the Mekong towns serve Vietnamese dishes such as naem nueang, grilled pork sausage wrapped at the table with herbs in rice paper.

Drinks are simpler: lao khao, a strong white rice spirit, and beer poured over ice.

The Khmer temples are the great sights of the south. Phimai, in Nakhon Ratchasima, stands in the centre of its old walled town, with its main tower in pale sandstone; Phanom Rung, in Buri Ram, crowns an extinct volcano, and at certain dawns and sunsets of the year the sun shines through all its doorways in a line. Prasat Muang Tam lies just below it. The forests of Khao Yai spill into Nakhon Ratchasima around Pak Chong.

In the centre and north, Khon Kaen has the nine-tiered stupa of Wat Nong Waeng and dinosaur finds at Phu Wiang, and Udon Thani has Ban Chiang's museum and excavation pit, the lake of Nong Han Kumphawapi, and the rock shelters of Phu Phrabat. Loei offers the plateau walk up Phu Kradueng and the Mekong town of Chiang Khan with its old wooden shophouses.

Along the Mekong, Nong Khai has Sala Kaeo Ku's giant concrete sculptures and the Friendship Bridge to Vientiane; Bueng Kan has the hilltop temple of Wat Phu Tok; Nakhon Phanom has the revered stupa of That Phanom; and Mukdahan has its riverside Indochina Market. The towns lead down to Ubon Ratchathani, where Khong Chiam marks the meeting of the Mun and Mekong rivers and Pha Taem's cliffs carry prehistoric paintings. Si Sa Ket's Wat Pa Maha Chedi Kaeo is built from millions of glass bottles.