SurindrarÃÂja () was an 11th-century Siamese monarch recorded in the Ayutthaya Testimonies as the ruler of Phraek Si Racha. At the age of 15, he succeeded his father, King Srisimha, at Phraek Si Racha circa 1050. Subsequently, he relocated the royal seat northward and established a new capital, which he named Chai Nat.
SurindrarÃÂja was the younger son of Queen SuchÃÂvatëdevë (), the principal consort of King à Ârësiá¹Âha. He had three siblings: the eldest, Jyeá¹£á¹ÂhakumÃÂra (à ¹Âà ¸Âà ¸©à ¸Âà ¸Âà ¸¸à ¸¡à ¸²à ¸£), who was also born to SuchÃÂvatëdevë but died in infancy, and two half-brothersâÂÂSà «ryavaá¹Âà Âa and AnurÃÂja âÂÂwho were born to the secondary queen consort, Suvaá¹Âá¹Âapabbata ().
SurindrarÃÂja is said to have ruled for 38 years before dying at the age of 53. He was married to Queen Candradevë (), though their union produced no issue. Following his death, the throne was inherited by his half-brother Sà «ryavaá¹Âà Âa in 1088. His reign is chiefly remembered for the establishment of Chai Nat as a royal and administrative center, and coincided with Pagan dominance over Suphannaphum in 1081, as well as its subsequent invasion of XiÃÂn at Ayodhya in 1087, which resulted in the death of Ayodhya's king Narai I that same year.