Emperor Wu of Northern Zhou
Yang Guang was born in 569, during the reign of Emperor Wu of Northern Zhou. His parents were Yang Jian, the Duke of Sui, and Yang Jian's wife Duchess Dugu Qieluo; his maternal grandfather was Dugu Xin, a prominent military general and official. He was his parents' second son, after Yang Yong, and he had at least one older sister, Yang Lihua, who became the wife of Emperor Wu's crown prince Yuwen Yun (the later Emperor Xuan) in 573. He was considered handsome and intelligent in his youth, and of Yang Jian's and Duchess Dugu's sons, they favored him the most. Sometime during Northern Zhou, on account of Yang Jian's achievements, he was created the Duke of Yanmen.