Before Thai pop existed, the most popular sound in the country had been traditional music played on locally created instruments. It was only during the Vietnam War, when Western music flowed into Thailand due to the U.S. military presence in the region, that the earliest ideas of Thai pop were formed.
Rock music, such as that of Elvis Presley and Cliff Richard & The Shadows, became a particular mainstay. Thai rock bands began mixing pleng lukgrung, or Thai urban music, with Western rock, infusing their own local sounds with the instruments and styles of the West. The traditional emphasis on woodwinds and brass gave way to electric guitars and keyboards, creating an entirely new style of music that would later become known as pleng string.
In the late 1960s, band competitions and live performances brought this new style to a wider local audience during a time when records and record players were expensive. Pleng string became most popular among younger audiences, who preferred modern Western sounds over traditional Thai music.