Yan Border Forces

Lore & Background

Yan's military doctrine was shaped by its unique geography and the constant pressure from northern nomads. Unlike states in the Central Plains, Yan faced a reality where defensive formations had to be solid yet flexible enough to handle rapid threats. The historian Wu Qi noted that "The Yan are a sincere and straightforward people... thus they excel in defensive positions, but are immobile and inflexible." To counter this, tactics involved applying pressure with small attacks and retreating rapidly to confuse their ranks. General Qin Kai expanded the kingdom's frontiers nearly one thousand kilometers east to the northwestern Korean Peninsula by launching campaigns against the Donghu and Gojoseon. This expansion led to the construction of a Great Wall on Yan's new northern borders. The forces also utilized currency shaped like knives, a form closely associated with nomads, suggesting deep commercial and tactical integration with the steppe tribes they fought.

In Their Own Story

In 227 BC, with Qin troops pressing on the border after the collapse of Zhao, Crown Prince Dan made a desperate move. He sent an assassin named Jing Ke to kill the King of Qin in Xianyang, hoping to end the threat forever. The mission failed, and Jing Ke died at the hands of the king. Enraged by this bold act, the King of Qin called on General Wang Jian to destroy Yan. The Qin army crushed the bulk of the Yan forces at the frozen Yi River. Ji, the capital, fell the following year, forcing King Xi to flee to the Liaodong Peninsula. Despite holding out in the north, the relentless Qin advance continued. In 222 BC, Liaodong fell as well, and Yan was overrun. This marked the end of Yan's independence, making it the third-to-last state to fall before Qin conquered all of China in 221 BC.

Reader's Guide

The State of Yan operated under a feudal system where regional lords contributed troops, though leadership could shift based on wartime merit, as seen when King Zhao plotted with Zhao, Qin, Han, and Wei to launch a joint expedition against Qi. The Border Forces were specifically tasked with defending the mountainous borders in the west between Zhao and Yan, an area that often saw clashes resulting in stalemates requiring outside intervention. A pivotal moment occurred in 314 BC when Qi invaded during a succession crisis started by King Zikuai's symbolic resignation to Minister Zizhi. Although Qi practically conquered the country in months, a revolt driven by the misconduct of Qi troops restored Yan's borders. Later, under General Yue Yi, Yan achieved a massive victory, capturing most of Qi's seventy walled cities within a year. However, strategy relied heavily on specific terrain advantages; as Wu Qi advised opponents: "Attack the rear as well where and when they least expect it... use our armored chariots to set ambushes." Ultimately, survival depended on these defensive adaptations until the final Qin conquest.

Did You Know?

• Yan established five commanderies—Shanggu, Yuyang, Youbeiping, Liaoxi, and Liaodong—to defend against the Donghu after expanding its frontiers eastward.
• General Qin Kai expanded Yan's territory nearly one thousand kilometers to the northwestern Korean Peninsula by defeating the Donghu and Gojoseon.
• Yan's currency was crafted in the shape of a knife, a form closely associated with northern nomads, likely for trade purposes.
• In 227 BC, Crown Prince Dan sent the assassin Jing Ke to kill the King of Qin in Xianyang, an act that precipitated Yan's final destruction.
• Yan was the third-to-last state to fall to Qin, finally overrun in 222 BC, just one year before the declaration of the Qin Empire.