, ruling from 916 to 926. He had a sinicised name,
; some sources suggest that Abaoji's family name, Yelü, was adopted during his lifetime, although there is no unanimity on this point.
Abaoji was born in 872 in Southern Mongolia and had a turbulent childhood. His grandfather was killed in a conflict between tribes, and his father and uncles fled. He was hidden by his grandmother for his safety. He became khagan of the Khitans on 27 February 907, and was subsequently enthroned as emperor of the Khitans in 916, proclaiming his own era name. He died on 6 September 926. He was responsible for the conquest and unification of all of Inner Mongolia, northern China and southern Manchuria. Once the Khitan Empire became the Liao dynasty in 942, he was posthumously considered a Liao emperor.
Legends surrounding Abaojis birth
Later generations of Chinese historians record a variety of legends that surrounded the birth of Abaoji. According to the legends, his mother Xiao Yanmujin dreamt that the sun fell from the sky and into her bosom, from which pregnancy followed. When she gave birth, the room was said to have become filled with a mysterious light and extraordinary fragrance. As a newborn, his body was that of a three-year-old, and the legends go on to say that he was walking at the age of three months. He was even recorded as being able to see events before they occurred.
Rise to power
The location of the Khitans in relation to the other neighbouring tribes is of importance. The Khitans resided on the east slope of the Greater Khingan Mountains. West of the mountains were other nomadic pastoral tribes such as the Shiwei and the Xi, along with the Turkic Uighur tribe. These other tribes had inter-married with the Khitans. Further west were the Tatars, a warlike tribe on the steppes of Mongolia. East and northeast lay the Jurchens all the way to the Amur river. They were a peaceful people that resided in small villages and subsisted by hunting and fishing. Across the Liao River to the east and southeast as far as the Yalu River lay the Balhae people, the majority of whom comprised a settled agricultural society.
The Yaolian clan had dominated the leadership of the Khitan tribes since the 750s. They maintained good relations with the Chinese Tang dynasty to the south. However, by the end of the ninth century, leaders of the powerful Yila tribe were expressing dissatisfaction with the Yaolian khans. Abaoji's father had been the elected chieftain of the Yila tribe. As surnames were considered a marker of Chinese culture, they were not used by the Khitan people outside of the Yaolian imperial clan.
Abaoji became chieftain of the Yila tribe in 901 and in 903, he was named the Yuyue, commander of all of the Khitan military forces. This had the effect of making him second only to the great khan in the hierarchy of the Khitan nation. He started making a name for himself in 905, when he led 70,000 cavalry into Shanxi to create a brotherhood with Li Keyong. Not only did he offer "brotherhood" but he pledged support against Zhu Wen. This showed that he was willing to be more aggressive than the Great Khan. In 907, he appeared at the triennial council and demanded to be named the khagan, the Khan of khans. His successes against the Chinese in the north, against whom he had been raiding since 901, led to him receiving the support of seven tribal chiefs and even the acquiescence of the last Yaolian Great Khan.
From 907 until 916, Abaoji was beset by constant uprisings and rebellions, mostly instigated by his own family members (cousins and brothers). He eventually won them over by persuading them that they could become more successful as a dynasty. With his walled city showing off the tribe's wealth and power, he appointed all the usurpers to positions of influence which placated them. Abaoji's skilful manipulation of his enemies allowed him to increase his own and his tribe's power.
Legacy
Abaoji's ongoing success was due to his ability to introduce innovations to Khitan society. Arguably the most important was the introduction of a dual administrative system in which nomadic steppe peoples would be governed by steppe traditions while sedentary populations in conquered Balhae and north China would be governed by a civil bureaucracy based largely on Chinese methods. While this did not receive universal support from tribal leaders due to the erosion of their own powers, this became the model that later steppe peoples would use to govern their diverse empires.
Two more important innovations were introduced in 916. He adopted Chinese court formalities in which he declared himself Celestial Emperor in the Chinese-style and adopted an era name, also in the Chinese manner of ruling. The second was to name his son, Yelü Bei, as his heir apparent, also a first in Khitan society and something that directly contrasted with Khitan notions of rule by merit. This second innovation did not take hold easily as only a few of his successors experienced simple successions.
He also organised his followers into warrior units known as orda, and then by joining 12 ordas together, he would form an administrative district.
In 918, Abaoji had a new walled city built. A Chinese city was built adjacent to this city in which artisan's shops, commercial shops, and warehouses were constructed. Later, five capital cities would be built, including a Supreme Capital (上京), that served as the base of Khitan administration.
Abaoji ordered the development of a Khitan large script in 920. This script looks superficially like Chinese writing, however, it bears little resemblance to Chinese writing, and the two were mutually unintelligible. Five years later, the arrival of a Uyghur delegation led Abaoji to order his younger brother, Yelü Diela, to develop a new script on more syllabic principles. Unlike the Japanese and Koreans, the Khitans managed to adopt the cultural and administrative tool of writing without the baggage of Chinese culture and grammar that came with the wholesale adoption of Chinese characters.
By the time he died of typhoid fever at the age of 54, Abaoji had captured the entire Balhae state, keeping their ruling family as nobility ruling his new fiefdom. His eastern boundaries were the Yalu River and the Ussuri River. His westward progression had gone far onto the Mongolian Plateau. By the time of his death, he had not acted on his plan to move south.
Relationship with the Later Tang
Li Cunxu, the son of Li Keyong who had formed a bond with Abaoji back in 905, founded the Later Tang on the ashes of the Later Liang in 923. On Li Cunxu's death, though relations between the two had soured, the proper forms were followed and an emissary was sent to the Khitan capital. The souring of relations occurred probably due to the aggressiveness of Abaoji, as in 922 and 923 he had pressed deep into Hebei, looting and taking prisoners all the way. This was in essence Later Tang territory.
Yao Kun
Yao Kun was sent by the Later Tang court to meet with Abaoji in 926. He caught up with the Khitan ruler in Manchuria while he was on campaign against the Balhae kingdom and while he was encamped at Fuyu in present-day Jilin Province. Abaoji demanded that the Later Tang surrender the Sixteen Prefectures. If they were given up, there would be no reason for Abaoji to invade China. Yao Kun stated that this demand was not in his authority to grant. This response landed him in prison, where he still was when Abaoji died from illness on September 6, 926.
Succession
Though Yelü Bei was designated heir apparent in 916, the empress dowager Shulü Ping did not consider him to be worthy and managed to have her second son Deguang succeed to the throne. Deguang became known to history as Emperor Taizong and he reigned from 926 to 947.
Family
Consorts and Issue:
• Empress Shulü Ping (述律平; 879–953), honoured as Empress Chunqin (淳钦皇后)
• Yelü Zhigu (耶律质古; d. 911)
• Married Xiao Shilu (萧室鲁; d. 911), a younger brother of Shulü Ping, and had issue (Xiao Wen)
• Eldest son Yelü Bei (耶律倍; 899–937), the Prince of Renhuang (人皇王), honoured with the temple name Yizong (义宗)
• Second son Yelü Deguang (耶律德光; 902–947), later Emperor Taizong of Liao
• Third son Yelü Lihu (耶律李胡; 911–960), honoured as Emperor Zhangsu (章肃皇帝)
• Court lady Xiao (萧氏)
• Fourth son Yelü Yaliguo (耶律牙里果)
Ancestry
辽太祖耶律阿保机（872年 - 926年），清辑本《旧五代史》改译安巴坚，汉名耶律亿，是大契丹国的第一位皇帝（916年3月7日－926年9月6日在位），在位10年。