Siddhijaya Brahmadeva

Siddhijaya Brahmadeva (, ) is described in legend as a ruler of Nakhon Chai Si, which has been identified with the present-day Nakhon Pathom, functioning as the center of Kamalanka. According to tradition, Siddhijaya consolidated authority in the region by suppressing a group of Brahmans, potentially led by Kakabhadra, who had exercised power over local settlements before Siddhijaya's arrival.

The Tanan and the mission from Lanka The narrative also recounts that news of the Tanan reached the king of Lanka, who dispatched a monk named Kalayadishthira to obtain the vessel in exchange for relics of the Buddha. Siddhijaya Brahmadeva requested the Tanan from the Brahmanical leaders, but his petition was refused. This refusal led to conflict between Siddhijaya and the Brahmanical community, compelling him to relocate to a nearby site where he established a new city, referred to in the sources as Pawan or Panan . There he constructed a large stupa—speculated by later tradition to be Phra Pathommachedi—to enshrine the relics received from the Lankan king. Eventually, Siddhijaya seized the Tanan by force and presented it to Kalayadishthira, the emissary from Lanka. and his grandsons are said to have been descendants of King Doṇabrāhmaṇa. No ruler is named in connection with these early embassies. The Chinese records that do name rulers of the polity they call Tou-he belong to the middle of the following century and are treated under Qizhangmo and Pu xie qi yao; no identification has been proposed between Siddhijaya and either figure.

Foundation of Lavapura During this period, it is recorded that Kalavarnadisharaja, the elder son of Kakabhadra, commissioned a group of Brahmans under his authority to construct the city of Lavapura in 629. The project was completed in 648. Having succeeded his father in 641, Kalavarnadisharaja subsequently relocated his seat to this newly established center and designated the polity as the Lavo Kingdom.