A Kingdom in Turmoil: The 1116 Liaodong Rebellion
The year 1116 marked a turning point in Northeast Asian geopolitics when a drunken rebellion in the Liao Dynasty’s eastern capital would set in motion events leading to the rise of the Jurchens. On the first day of the lunar new year, Gao Yongchang, a disgruntled Bohai official, led a band of rebels in assassinating Xiao Baoxian, the Liao governor of Liaoyang. This sparked widespread unrest among the Bohai people, descendants of the fallen Balhae kingdom who had long chafed under Khitan rule.
Within days, Gao declared himself emperor of a revived Bohai state, seizing control of fifty prefectures across Liaodong. The rebellion exposed the Liao Dynasty’s weakening grip on its frontier territories. More significantly, it created an opening for the Jurchen chieftain Wanyan Aguda (Emperor Taizu of Jin) to expand southward from his Manchurian homeland. When Gao sought Jurchen assistance against Liao forces, the Jurchens first pretended to help before turning on their would-be ally, capturing strategic cities like Shenzhou (modern Shenyang).
The Song Court’s Divided Counsel
News of the Jurchen victories reached the Song capital Kaifeng, reigniting debates about recovering the lost Sixteen Prefectures. Emperor Huizong’s court split between hawks like the eunuch commander Tong Guan, who advocated military action, and doves who warned against breaking the century-old peace with Liao.
The timing proved problematic. Huizong was diverting enormous resources to his extravagant projects – constructing the Genyue imperial garden and Daoist temples. To fund these, his ministers implemented exploitative policies like the “Public Fields” system that converted peasant lands into imperial property. When military envoy Tao Yue returned from Liao in 1117 reporting no imminent threat, Huizong temporarily shelved invasion plans.
The Maritime Connection
In 1117, a chance maritime encounter changed everything. Two ships carrying over 200 refugees from the conquered Liao territory of Suzhou (modern Dalian) drifted to Song shores. Their leader, Gao Yaoshi, revealed that the Jurchens now controlled coastal regions facing Shandong. This meant only the Bohai Sea separated Song from Jurchen territory.
Seizing the opportunity, Huizong dispatched multiple embassies to Aguda’s court. The first, led by Ma Zheng in 1118, established initial contact. The more significant 1120 mission by Zhao Liangshi (a former Liao official defected to Song) negotiated the terms of what became known as the “Sea Alliance.”
The Terms of the Pact
After witnessing the Jurchens’ stunning capture of Liao’s Supreme Capital in just half a day, Zhao negotiated an agreement where:
– Song would receive the Sixteen Prefectures south of Yan Mountains
– Both sides would launch coordinated attacks on Liao
– Neither would make separate peace with Liao
– Song would transfer its annual tribute (500,000 units of silver and silk) from Liao to Jin
However, critical ambiguities remained regarding the western prefectures and three northeastern districts (Ping, Luan, Ying) not part of the original Sixteen Prefectures ceded in 937.
The Unraveling
The alliance quickly faced challenges. In 1121, Song failed to mobilize its promised attack due to domestic rebellions. When the Jurchens single-handedly captured Yanjing (Beijing) in 1122, they initially refused to hand it over, citing Song’s nonperformance. Only after protracted negotiations and additional payments did a reduced Song force occupy the devastated city in 1123.
The partnership collapsed completely after Aguda’s death in 1123. His successor viewed the Song as weak and duplicitous. In 1125, after finishing off the Liao, the Jurchens turned south, launching an invasion that would culminate in the Jingkang Incident of 1127 – the fall of Kaifeng and the captivity of Emperor Huizong and Qinzong.
Legacy of a Fateful Decision
The Sea Alliance represents one of history’s most consequential failed partnerships. For the Jurchens, it provided legitimacy and strategic advantage against Liao. For Song, it became a cautionary tale about short-sighted diplomacy. The hawks had underestimated Jurchen ambition while overestimating Song’s military capability.
The episode also revealed the Song court’s dysfunction – its distraction by imperial extravagance, exploitative fiscal policies, and the emperor’s vacillation between hawkish advisors and more prudent voices like An Yaochen, who had warned that “when lips perish, teeth grow cold.”
Ultimately, the attempt to exploit Liao’s weakness brought the far more formidable Jurchens to the Yellow River, setting the stage for the Southern Song’s eventual retreat south of the Yangtze. The Sea Alliance’s legacy endures as a textbook case of miscalculated realpolitik with catastrophic consequences.