Chrakavarman I was born on December 5 as Rengsei, the son of Emperor Samhanaopetavarman III and his wife Empress Indradevi. He was their first child and son and was the crown prince and heir apparent. When he was one year his brother Prince Serey was born. He went to school in the Angkor Imperial School, which was the most prestigeous school in the entire empire. He was a smart student and made many friends.