Go to one of the huge luk thung shows held in a temple or local stadium on the outskirts of Bangkok, or to any temple fair in the countryside, and you'll hear one of the great undiscovered popular musics of Asia. The shows, amid the bright lights, foodstalls and fairground games, last several hours and involve dozens of dancers and costume changes. In contrast with luk grung, luk thung (literally, "child of the field") has always been associated with the rural and urban poor, and because of this has gained nationwide popularity over the past forty years.

According to luk thung DJ Jenpope Jobkrabunwan, the term was first coined by Jamnong Rangsitkuhn in 1962, but the first song in the style was Oh Jow Sow Chao Rai (Oh, the Vegetable Grower's Bride), recorded in 1937, and the genre's first big singer, Kamrot Samboonanon, emerged in the mid-1940s. Originally called pleng talat (market songs) or pleng chiwit (songs of life), the style blended together folk songs (pleng phua bahn), central Thai classical music and Thai folk dances (ram wong). Malay strings and fiddles were added in the 1950s, as were Latin brass and rhythms like the cha-cha-cha and mambo (Asian tours by Xavier Cugat influenced many Asian pop styles during the 1950s), as well as elements from Hollywood movie music and "yodelling" country and western vocal styles from the likes of Gene Autry and Hank Williams. In 1952, a new singer, Suraphon Sombatjalern, made his debut with a song entitled Nam Da Sow Vienne (Tears of the Vientiane Girl) and became the undisputed king of the style until his untimely murder (for serious womanizing, rumour has it) in 1967. Sombatjalern helped develop the music into a mature form, and was known as the "King" of the genre, along with his Queen, sweet-voiced Pongsri Woranut.

Today, luk thung is a mix of Thai folk music and traditional entertainment forms like likay (travelling popular theatre), as well as a range of Western styles. There are certainly some strong musical affinities with other regional pop styles like Indonesian dangdut and Japanese enka, but what is distinctly Thai – quite apart from the spectacular live shows – are the singing styles and the content of the lyrics. Vocal styles are full of glissando, wavering grace notes and wailing ornamentation. A singer must have a wide vocal range, as the late luk thung megastar Pompuang Duangjan explained: "Making the luk thung sound is difficult, you must handle well the high and low notes. And because the emotional content is stronger than in luk grung, you must also be able to create a strongly charged atmosphere."

Pompuang had the kind of voice that turns the spine to jelly. She rose to prominence during the late 1970s, joining Sayan Sanya as the biggest male and female names in the business. Like Sombatjalern, both came from the rural peasantry, making identification with themes and stories that related directly to the audience much easier. Songs narrate mini-novellas, based around typical characters like the lorry driver, peasant lad or girl, poor farmer, prostitute or maid; and the themes are those of going away to the big city, infidelity, grief, tragedy and sexual pleasure. Interestingly, it is not always the lyrics that carry the sexual charge of the song (and if lyrics are deemed too risqué by the authorities the song will be subject to strict censorship) but rather the vocal style and the stage presentation, which can be very bawdy indeed.

With the advent of TV and the rise in popularity of string, the number of large upcountry luk thung shows has declined. It's not easy, said Pompuang, to tour with over a hundred staff, including the dancers in the hang kruang (chorus). "We play for over four hours, but string bands, with only a few staff members, play a paltry two hours!" Her response to the advent of string and the increasing importance of promotional videos was to develop a dance-floor-oriented sound – electronic luk thung. Few luk thung singers are capable of this, but Pompuang had the vocal range to tackle both ballad forms and the up-tempo dance numbers. Her musical diversification increased her popularity enormously, and when she died in 1992, aged only 31, up to 200,000 people, ranging from royalty to the rural poor, made their way to her funeral in her home town of Suphanburi.

Since Pompuang's death, the top luk thung slot has been occupied by "Got" Chakrapand Arbkornburi, whose switch from pop to full-time luk thung has brought many younger listeners to the style, while the reigning female singer was Suranee Ratchasima but she has been superseded by the perkier Arpaporn Nakornsawan. Mike Piromporn, originally a mor lam man, is Got's main challenger. Bangkok's first 24-hour luk thung radio station, Luk Thung FM (at 90 FM), was launched in 1997, and it's even hip for the middle class to like luk thung these days. Listeners have been snapping up collections of luk thung classics, and several veteran singers have relaunched their careers, including Sodsai Rungphothong, who had a monster two-million seller with his Rak Nong Porn album. A new generation of singers has also emerged, with artists like Monsit Kamsoi, Yingyong Yodbuangarm, Yui Yardyuh,Tai Orathai and Fon Thanasunthorn. There is some truth, however, in the criticism that some new luk thung stars are being artificially manufactured just like their pop and rock counterparts, and there's a tendency to rate a pretty face over vocal expertise.

For many years, luk thung was sung by performers from the Suphanburi area in the central plains, but more regional voices are being heard in the genre now, with northeasterners now outnumbering these singers. A slightly faster rhythm, luk thung Isaan, has developed, led initially by Pimpa Pornsiri, who called the style luk thung prayuk. The south, too, has its own luk thung star, in the enormously popular Ekachai Srivichai. But the most surprising development has been the emergence of not one but two blonde-haired, blue-eyed foreigners singing luk thung and mor lam. First up is Swede Manat "Jonas" Andersson, who rose to national prominence with his debut album, Pom Cheu Jonas – he's already a fixture on the luk thung circuits; meanwhile, Anglo-Dutch singer Kristy Gibson sings mainly luk thung Isaan and mor lam.