King Suryavarman I

Suryavarman I (Khmer: សូរ្យវរ្ម័នទី១; posthumously Nirvanapada) was king of the Khmer Empire from 1006 to 1050. Suryavarman usurped King Udayadityavarman I, defeating his armies in approximately 1002. After a protracted war with Udayadityavarman's would-be successor, Jayavarman, Suryavarman I claimed the throne in 1010. Suryavarman was the son of the king of Tambralinga, a minor Buddhist kingdom on the Malay peninsula (present-day Thailand) that was a dependent of Angkor's rival Srivijaya. Suryavarman held claim to the Khmer throne through his Khmer mother who was a member of the royal family. While the Khmer Empire predominantly practiced Vaishnava Hinduism, Devaraja, Suryavarman was a Mahayana Buddhist who was also tolerant of the growing Theravada Buddhist presence in the Khmer kingdom.

Suryavarman I established diplomatic relations with the Chola dynasty of south India around 1012. Suryavarman I sent a chariot as a present to the Chola Emperor Rajaraja Chola I. It seems that the Khmer king Suryavarman I requested aid from the powerful Chola Emperor Rajendra Chola against Tambralinga kingdom . After learning of Suryavarman's alliance with Rajendra Chola, the Tambralinga kingdom requested aid from the Srivijaya king Sangrama Vijayatungavarman. This eventually led to the Chola Empire coming into conflict with the Srivijiya Empire. The war ended with a victory for the Chola dynasty and Angkor Wat of the Khmer Empire, and major losses for the Sri Vijaya Empire and the Tambralinga kingdom.

His reign lasted some 40 years and he spent much of that time defending it. Known as the "King of the Just Laws," he consolidated his political power by inviting some four thousand local officials to the royal palace and swear an oath of allegiance to him. Suryavarman I favored Buddhism but he allowed the people to continue practising Hinduism. His palace was situated in the vicinity of Angkor Thom, and he was the first of the Khmers rulers to protect his palace with a wall.

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