History

The city of Nakhon Si Thammarat is one of the oldest towns of southern Thailand. Its origins are not fully known. Most historians recognize the Tambralinga kingdom of Chinese records as a precursor of Nakhon Si Thammarat. The town chronicles of this time are hardly separable from legend, but they do tell of an abandonment and refounding of the town, which would explain the break in history between Tambralinga and Nakhon Si Thammarat.
References to a country named Poling appear in Chinese chronicles from the Tang dynasty period down to the early Ming dynasty. Many scholars identify Poling with Maling and Danmaling was one of the member-states of Sanfoqi (mean Srivijaya in Chinese language) in the central part of the Malayu Peninsula or now a day the southern Thailand. Consequently, Poling may also be equated to the Tambralingarat (Tambralinga state) that appear in Indian sources. By the end of the 12th century, Tambralinga had become independent of Srivijaya kingdom. Its rapid rise to prominence since the 13th century till the beginning of 14th century, Tambralinga had occupied the entire Malay Peninsula and become one of the dominant Southeast Asian states. By the end of the 14th century, Tambralinga had become a part of Siam (Thailand now a day) named Nakhon Si Thammaraj.
At the time of the Sukhothai kingdom, the Nakhon Si Thammarat kingdom was already listed as one of the kingdoms under control of the Thai, which it has remained during most of its history. It was usually known as Ligor to European merchants in the 16th century. At the end of the 19th century, the kingdom was finally fully absorbed into Siam by converting it into the Monthon Nakhon Si Thammarat. With the abolishment of the monthon system in 1932, the town now is simply a provincial capital.

Source: http://en.wikipedia.org/wiki/Nakhon_Si_Thammarat