The Fractured Landscape of Post-Qin China

The collapse of the Qin Dynasty in 206 BCE left a power vacuum that ignited one of history’s most dramatic power struggles. As regional warlords carved up the former empire, two titans emerged: Xiang Yu, the militarily brilliant but politically inflexible “Hegemon-King of Western Chu,” and Liu Bang, the pragmatic former peasant official who would found the Han Dynasty. This era of competing kingdoms—briefly numbering seven before consolidating into the Chu-Han dichotomy—witnessed extraordinary political maneuvering, where personal loyalties and geographic strategy determined the fate of nations.

At the heart of this conflict lay the strategic Korean region (旧韩国), whose control became crucial for eastward expansion. When Xiang Yu appointed Zheng Chang—a descendant of the old Zheng nobility—as King of Han (韩王), it was a masterstroke of political theater. By installing a leader with ancestral ties to the region, Xiang Yu sought to legitimize his rule over this buffer state against Liu Bang’s westward ambitions.

The Chessboard of War: Key Figures and Turning Points

The political landscape shifted dramatically with the arrival of two pivotal figures at Liu Bang’s camp in 205 BCE: Zhang Er, the ousted King of Changshan, and Zhang Liang, the brilliant strategist who had previously served the Korean court. Their defections weren’t merely personal tragedies but strategic windfalls.

Zhang Er’s history with Liu Bang dated back to their youth as wandering knights during the Warring States period. Now, decades later, their reunion proved militarily decisive. As former commander of Zhao forces under Xiang Yu, Zhang Er brought critical intelligence about the defenses of Henan (河南国). His personal connections with Shen Yang, the Henan king who controlled the vital Hangu Pass approach, enabled Liu Bang to breach Xiang Yu’s first defensive line without major bloodshed.

Meanwhile, Zhang Liang’s return allowed Liu Bang to exploit ethnic politics in Korea. By promoting Han Xin (not to be confused with the famous general) as a rival Korean claimant, Liu Bang undermined Zheng Chang’s legitimacy. The campaign culminated in the siege of Yangcheng (modern Dengfeng), where Korean forces, torn between two claimants, offered limited resistance.

The Cultural Undercurrents of Power

Beyond battlefield tactics, this conflict revealed deeper sociopolitical currents. The careful management of religious symbols—such as Liu Bang’s replacement of Qin state altars with Han ones—demonstrated an acute awareness of cultural governance. This ritual transition from Qin to Han社稷 (state altars) served as psychological preparation for regime change among the populace.

The episode of Chen Ping’s youth—where his fair division of sacrificial meat earned local admiration—encapsulates the era’s social values. Such community rituals (乡里社祭) weren’t merely religious observances but crucial forums for demonstrating leadership qualities. Similarly, Liu Bang’s administrative reforms—appointing local elders (三老) as intermediaries between government and villages—show how wartime rulers sought grassroots legitimacy.

The Intelligence War: Shadows Behind the Throne

Modern historians often overlook the clandestine dimension of the Chu-Han contention. Chen Ping’s role as head of the 护军中尉府 (Protectorate of the Central Army) represented one of history’s earliest formalized military intelligence agencies. His network likely facilitated critical defections—including Zhang Er’s—and ensured Liu Bang’s awareness of Xiang Yu’s movements.

This shadow war proved decisive when Xiang Yu made his legendary forced march from Qi to retake Pengcheng (彭城之战). While traditional accounts focus on the 30-day, 500-kilometer blitzkrieg, the absence of logistical details suggests successful Han intelligence operations in obscuring their own vulnerabilities. The subsequent rout—where 100,000 Han-aligned troops perished in the Si River—demonstrated both armies’ reliance on information control.

The Legacy of a Pivotal Year

The events of 205-204 BCE marked the true beginning of systemic warfare between Chu and Han. Liu Bang’s consolidation of Guanzhong as a productive base (via Xiao He’s administration) contrasted with Xiang Yu’s overextension across multiple fronts. The failed attempt to extract family members from Chu territory—foiled at Yangxia—revealed the personal stakes underlying this geopolitical struggle.

Most significantly, these campaigns established the operational template for Liu Bang’s eventual victory: leveraging defectors from Xiang Yu’s camp, exploiting ethnic identities within conquered territories, and maintaining relentless pressure on multiple fronts. When the Han Dynasty finally triumphed in 202 BCE, its governance structure—blending centralized control with regional flexibility—bore the imprint of lessons learned during these critical campaigns.

The Chu-Han contention’s modern relevance lies in its demonstration of how cultural legitimacy, intelligence superiority, and administrative competence ultimately outweigh pure military brilliance—a lesson echoing through two millennia of Chinese statecraft.