Chandrabhanu (died 1270?) or Chandrabhanu Sridhamaraja was the King of the Malay state of Tambralinga in present day Thailand. He was known to have ruled from during the period of 1230 until 1270. He was also known for building a well-known Buddhist stupa in southern Thailand. He spent more than 30 years in his attempt to conquer Sri Lanka. He was eventually defeated by Pandyan forces from South India in 1270.

In 1247 he sent an expedition to the island ostensibly to acquire the Buddhist relict from the island. His forces, using poison darts, were able to occupy the northern part of the island. In 1253 his forces faced an invasion of the island by Pandyan forces. In 1258 Tambralinga forces commanded by his son and two Sinhalese princes were defeated by the Pandyans. In 1270 he invaded the island once again, only to be defeated decisively by the Pandyans. The defeat was so complete that in 1290, Tambralinga was absorbed by the neighboring Thai Kingdoms. Bennett, Mathew The Hutchinson Dictionary of Ancient and Medival warfare, p.100

Tambralinga

According to the inscription no.24 found at wat Hua-wieng (Hua-wieng temple) in Chaiya near to Nakhon Si Thammaraj, Chandrabhanu is a ruler of Tambralinga and was of Patama vamsa (lotus dynasty). He began to reign in 1230, he had built the Phrae Boromadhatu a buddhist stupa in Nakhon Si Thammaraj to hold the Buddha's relict.

First invasion of Sri Lanka

It was recorded by the Mahawamsa, the historic chronicle of Sri Lanka to have invaded Sri Lanka in 1247 in search of Buddha's relict that Sri Lanka already had. According Sri Lankan sources he was a Javaka chieftain and a sea pirate from the kingdom of Tambralinga. Although one Parakramabahu II (1236-70) from Dambadeniya was able to defeat him, Chandrabhanu moved north and secured the throne for himself around 1255. This prompted the Pandyan Empire in South India to intervene. They forced Chandrbhanu to submit to Pandya rule in 1253.

Second invasion

When Chandrabhanu embarked on a second invasion of the south, the Pandyas again came to the support of the Sinhalese king and defeated Chandrabhanu's forces in 1270. However, to further the power of Tamil hard power in the region, they eventually installed one of their ministers in charge of the invasion, one Aryacakravarti as the King.de Silva, A History of Sri Lanka, p.91-92 In the local Tamil language, all South East Asians are known as Javar or Javanese. There are number of place names in the Jaffna peninsula which pertains to its South East Asian connections. Chavakacheri means a Javanese settlement. Chavahakottai means a Javanese fort all alluding to Chandrabhanu's brief rule in the north.