The Fragile Alliances of a Divided Empire

The early years of the Han dynasty’s formation were marked by shifting loyalties and precarious power balances. Following the collapse of the Qin dynasty, China fractured into rival kingdoms, with Xiang Yu of Chu and Liu Bang of Han emerging as the primary contenders. This era, known as the Chu-Han Contention (206-202 BCE), witnessed not just military clashes but also intense diplomatic maneuvering.

At this critical juncture, the allegiance of regional warlords like Ying Bu, King of Jiujiang, held strategic importance. Ying Bu, a former Chu general who had been enfeoffed as an independent king, commanded significant forces in the Yangtze valley. His territory served as both a buffer and potential launching point between the Chu and Han power bases.

The Diplomatic Gambit: Sui He’s Mission to Jiujiang

Liu Bang’s strategist Zhang Liang identified Ying Bu as the linchpin that could alter the war’s momentum. The task of persuading this formidable warlord fell to Sui He, a lesser-known but exceptionally skilled diplomat. Arriving at Jiujiang’s capital in 205 BCE, Sui He faced immediate obstruction—Ying Bu kept him waiting for three days while hosting lavish banquets through his Grand Steward, avoiding substantive discussion.

Recognizing the king’s hesitation, Sui He executed a masterstroke of psychological pressure. He told the Grand Steward:

“If the king refuses my audience because he perceives Chu as strong and Han as weak, then hearing my analysis is precisely why I came. Should my words prove worthless, let the king execute me and my twenty attendants in the marketplace to demonstrate his loyalty to Chu.”

This bold ultimatum forced Ying Bu’s hand. When finally admitted to court, Sui He systematically dismantled the king’s rationale for supporting Xiang Yu through a four-pronged argument:

1. Moral Legitimacy: Highlighting Xiang Yu’s regicide against Emperor Yi of Chu
2. Strategic Vulnerability: Exposing Chu’s overextension in multiple fronts
3. Military Reality: Demonstrating Han’s defensive preparations along the Yingyang-Chenggao line
4. Personal Incentive: Promising territorial expansion beyond Jiujiang

The Turning Point: Forcing Ying Bu’s Hand

The diplomatic encounter reached its climax when Chu envoys arrived demanding Jiujiang’s military support against Han. Sui He made a dramatic intervention during their audience, publicly declaring Ying Bu’s allegiance to Han—a masterful fait accompli that left the king no retreat.

This forced Ying Bu to execute the Chu envoys and openly rebel against Xiang Yu. The consequences were immediate and profound:

– Xiang Yu had to divert forces under generals Long Ju and Xiang Sheng to suppress Jiujiang
– This bought Liu Bang crucial time to consolidate defenses at Yingyang
– Chu’s southern flank became permanently vulnerable

The Ripple Effects: Military and Psychological Impacts

Ying Bu’s defection created cascading effects beyond the battlefield:

1. Cavalry Revolution: The Han army, recognizing cavalry’s importance after defeats, formed its first dedicated cavalry corps under Guan Ying
2. Cultural Integration: Overcoming tensions between original Chu officers and assimilated Qin cavalry specialists
3. Strategic Reorientation: Transforming Han from reactive defense to coordinated multi-front warfare

The psychological blow to Xiang Yu proved equally significant. His most feared general had not just abandoned him but become a mortal enemy. This erosion of aura would culminate three years later at Gaixia, where Ying Bu’s forces would help corner the Chu hegemon.

Legacy of a Diplomatic Masterstroke

Sui He’s achievement represents one of history’s most successful diplomatic coups. His methods—combining strategic insight, psychological acuity, and calculated brinkmanship—would echo through Chinese history. Notably, Ban Chao employed similar tactics centuries later during his Western Regions campaigns.

The aftermath revealed deeper truths about Han’s emerging political order. At a post-victory banquet, Liu Bang initially dismissed Sui He as a “pedantic scholar”—until the diplomat reminded him that his twenty-man mission had achieved what 50,000 troops could not. This episode encapsulates the tension between martial culture and administrative merit that would characterize early Han governance.

Conclusion: Diplomacy as Warfare by Other Means

The Jiujiang mission demonstrates how individual diplomatic brilliance could reshape grand strategy. Sui He’s understanding of human nature—Ying Bu’s fears, Xiang Yu’s weaknesses, Liu Bang’s needs—proved as decisive as any battlefield engagement. In the end, this obscure diplomat’s achievement ensured that when Xiang Yu made his final stand at the Wu River, he did so encircled by former allies in lands that should have been his heartland—a testament to the enduring power of persuasive statecraft.