Liao Dynasty (907-1125 AD) was an empire in eastern Asia that ruled by the Yelu family of the Khitan people. The dynasty was establish in the final year of the Tang Dynasty but was annihilated by the Jin Dynasty in 1125.

The Khitan minority was an ancient nomadic tribe that lived in Northern China. They were first mentioned in historical records in 389 during the Northern Wei Period.As early as the 4th century, C.E., the Khitan, like other pastoral nomads, depended largely on their animals for survival, though a few tribes supplemented their incomes by fishing and farming.

By the early 7th century they sought to establish their own state on China's frontier but failed due to the strong Tang resistance (618-907). As a result, the Khitan tribe was brought under Chinese rule. After the decline of the Tang, the Khitan tribe frequently attacked its neighbors, capturing people from other states that rapidly boosted its power.

In 916, Yelu Abaoji, the chief of the Khitan tribe, established the Khitan Kingdom and proclaimed himself emperor. Historically, Yelu Abaoji was called Emperor Taizu. Two years later, Yelu Abaoji based his capital north of the Xar Moron River and named it Huangdu (imperial capital).
In 947, Emperor Taizong renamed his dynasty the "Great Liao". In 983, Emperor Shengzong revived the name Khitan. In 1066, Emperor Daozong restored the name "Great Liao."
After the founding of the kingdom, Abaoji gradually conquered its weak neighboring tribes. In 926, he conquered the Uigurs in Ganzhou and captured the Bohai State.
Emperor Taizong (Yelu Deguang) reigned from 926 to 947. During this period, the Liao Dynasty reached Manchuria and the sixteen prefectures below the Great Wall from the Mongolian border. The area south of the Great wall remained outside Chinese control for more than 400 years. Although this posed a threat to the Northern Song (960-1127), the region acted as a center for cultural exchanges between the Chinese and northern peoples during the period.
After obtaining the sixteen prefectures, the Liao based its alternate capital in Yanjing (today’s Beijing). Taking Yanjing as its base, the Liao began its expansion to the Central Plains. In 946 it took Kaifeng, the capital of the Song Dynasty, and proceeded to attack the weak troops of the civil-oriented Song government. However, due to strong resistance in the Central Plains, the attempt was abandoned.

How did Liao Dynasty end?

Following the prosperity enjoyed during the reigns of Emperor Shengzong and Xingzong, the Liao Dynasty declined. In the early years of the 12th century, the Jurchen tribe gradually grew in strength and became a great threat to the Liao. In 1115, the Jurchen established its own dynasty, the Jin Dynasty (1115-1234), with Aguda as the emperor. In the same year, the Jin army captured Huanglong, a strategically important town of the Liao. Later, the Jurchen established an alliance with the Song to attack the Liao.
The Liao government, weakened by economical disasters and internal quarrels, became brittle. Quickly, the Jin army occupied most of the Liao territory. In 1125, Emperor Tianzuo was captured by the Jin army, which brought the Liao Dynasty to an end. In 1131, Yelu Dashi, a minister of the former Liao, re-established the Liao in the Chuhe valley which became known as the Western Liao. In 1218, the Mongols conquered the kingdom of Western Liao.

Politics
The Liao employed a differential ruling system where different systems were applied to people from different cultures and economies in different areas. The administration system mainly consisted of the tribal, slavery, Bohai and feudal systems for the Han people.

The Khitan people adapted the tribal system in which they maintained their traditional rites and, to a great extent, retained their own style of cooking and dress. For the Han people, particularly in the farming regions, the Tang’s system was imposed. It included the use of Tang official titles, an examination system for the appointment of civil service and a Chinese-style tax regime. The Chinese language continued to be used and the customs of the Han were also preserved.
Officials were divided into two groups, according to their origin (north or south). Corresponding administration systems were set up for each area. The Khitan administrative system, called the orthodox system, was applied to northern Khitan officials, while the southerners used the Han system. Because of the different customs and levels of economic development, the northern officials mainly governed the Khitan Tartars and other nomadic peoples, while the southern officials took charge of agriculture mainly in areas where Han people resided. Since the Liao Dynasty was founded by the Khitan, the northern officials were considered superior, but the southern administrative system was actually the feudal system that was practiced in the Central Plain states. After the Liao conquered the sixteen prefectures in the Yanyun area, the system was improved.

Culture

Culturally, the Liao achieved much in astronomy, the calendar, medicine and architecture. Liao calendar retained the best parts of the Central Plain Han calendar and also kept some of the special traits of the Khitan people. Important achievements were made in acupuncture, pulse-feeling diagnosis, gynecology, obstetrics and the preservation of corpses. The Book of Acupuncture and Pulse-Feeling, written by a celebrated doctor named Zhi Lugu, enjoyed wide popularity at the time.
Liao architecture was influenced by the Tang and accommodating Khitan customs, achieved its own unique style. While the Liao honored Confucian philosophy, the rulers patronized Chinese Buddhism. The Khitan dialect and the Han language were the main languages of the Liao.