Yelü Deguang (耶律德光), also known as Emperor Taizong of Liao (遼太宗), was the second emperor of the Liao Dynasty, a Khitan-led empire that ruled over parts of northern China and Inner Asia from 916 to 1125. Born on November 25, 902, with the personal name Yaogu (堯骨) and courtesy name Dejin (德謹), he was the second son of Yelü Abaoji, the founder and first emperor (Emperor Taizu) of the Liao Dynasty, and his wife Shulü Ping. His birth occurred before the formal establishment of the dynasty, during a period when the Khitan tribes were consolidating power under his father's leadership.
As a young man, Yelü Deguang was described in historical records, such as the History of Liao (遼史), as having a serious demeanor and a kind disposition. He actively participated in his parents' administration of the emerging Khitan state, demonstrating early aptitude for governance and military affairs. In 922, during his father's reign, he was appointed as the Generalissimo of All Forces (天下兵馬大元帥), a high military command that placed him in charge of leading incursions into the territory of the Former Jin dynasty, the Khitans' southern neighbor. These raids were part of the broader strategy to expand Khitan influence and secure tribute from Chinese states.
Following the death of Yelü Abaoji in 926, Yelü Deguang ascended to the throne as Emperor Taizong, succeeding his elder brother Yelü Bei, who had been designated heir but fled to the Later Tang dynasty amid internal strife. His reign (926–947) marked a period of aggressive expansion and military success for the Liao Dynasty. Yelü Deguang transformed the Khitan from nomadic confederates into a formidable imperial power, dominating rival Chinese dynasties during the chaotic Five Dynasties and Ten Kingdoms period.
One of his most notable achievements was the conquest of the Later Jin dynasty. In 946, allying with Shi Jingtang, a disaffected Jin general, Yelü Deguang launched a campaign that captured the Jin capital, Luoyang, and forced the Jin emperor Shi Chonggui to submit. Yelü Deguang entered the city in 947, proclaiming himself emperor of China and adopting the reign name Tianluan (天祿). He extracted significant concessions, including the cession of the Sixteen Prefectures (a strategic region south of the Great Wall) and annual tribute of 300,000 bolts of silk. However, his ambitions to fully incorporate Chinese territories led to overextension.
During the retreat from Luoyang later in 947, Yelü Deguang fell ill, possibly from heatstroke or poisoning, and died on May 18, 947, at the age of 44, near present-day Datong in Shanxi. His death sparked a succession crisis, with his nephew Yelü Ruan briefly taking power before Yelü Dashi and others stabilized the dynasty. Posthumously honored as Emperor Taizong, his tomb is located in present-day Inner Mongolia.
Yelü Deguang's legacy includes the solidification of the Liao Dynasty as a dual-system empire blending Khitan nomadic traditions with Chinese bureaucratic elements. He promoted sinicization among the elite while maintaining Khitan military supremacy. His campaigns against the Former Jin, Later Jin, and other states expanded Liao territory significantly, influencing the balance of power in East Asia for centuries. Historical sources portray him as a capable general and administrator, though his overambitious invasion of China is often critiqued as a strategic misstep.
Key family members include his elder brother Yelü Bei, who was killed in 937 after defecting to the Later Tang; his consort Shulü Ping (his mother, but consorts during reign); and successors like Yelü Ruan (Emperor Shizong). The Liao Dynasty under his rule controlled vast steppes and agricultural heartlands, fostering a multicultural empire.
Sources consulted include the History of Liao and modern analyses. For further reading: