Digunai was the second son of Woben (斡本; also known as Wanyan Zonggan 完顏宗幹), a son of Aguda (Emperor Taizu), the founder of the Jin dynasty. His mother was, Lady Da, came from an elite family of Balhae descent. Emperor Taizu's brother and successor, Emperor Taizong, started a series of wars between the Jin and Song dynasties. During the reign of Emperor Xizong, who succeeded Emperor Taizong, Wanyan Zonggan was described as the most influential man in the Jin imperial court.