The Imjin War and Ming China’s Intervention

The late 16th century witnessed a dramatic shift in East Asian geopolitics when Toyotomi Hideyoshi, having unified Japan after centuries of civil war, set his sights on continental conquest. In 1592, Japan launched a massive invasion of Korea, marking the beginning of what would become known as the Imjin War. The Korean peninsula, caught unprepared, saw its capital Seoul fall within weeks as Japanese forces advanced rapidly northward toward the Yalu River.

Ming China, Korea’s suzerain state and the dominant power in the region, initially hesitated to commit substantial forces. The Wanli Emperor’s court debated the appropriate response to what many viewed as a regional disturbance rather than an existential threat. However, as Japanese troops approached China’s borders and Korean pleas grew more desperate, the Ming leadership recognized the strategic imperative to act. The Japanese conquest of Korea would give Hideyoshi a foothold on the Asian mainland, directly threatening Ming territory.

Li Rusong: The Ming Dynasty’s Formidable Commander

Into this crisis stepped Li Rusong, scion of a distinguished military family from Liaodong. The Li clan had maintained China’s northern frontiers for generations, producing exceptional cavalry commanders adept at combating both Mongol raiders and Jurchen tribes. Li Rusong embodied this martial tradition, having distinguished himself in numerous campaigns along the Great Wall frontier.

The Ming court appointed Li Rusong as chief commander of expeditionary forces to Korea, a decision that would prove decisive. Li brought with him the elite Liaodong cavalry – hardened frontier troops whose combination of mobility and firepower made them arguably the finest fighting force in East Asia. Their signature weapon, the three-eyed gun (三眼神铳), allowed them to deliver devastating volleys before closing with their enemies using the same weapon as a club.

The Liberation of Pyongyang and Rapid Advance

Li Rusong’s campaign began spectacularly with the siege of Pyongyang in January 1593. Despite being outnumbered, Li’s forces employed clever stratagems and overwhelming firepower to dislodge Konishi Yukinaga’s garrison from the fortified city. The victory at Pyongyang shattered Japanese morale and demonstrated the qualitative superiority of Ming troops.

What followed was one of the most remarkable advances in military history. As news of Pyongyang’s fall spread, Japanese garrisons across northern Korea abandoned their positions without fighting. Huangzhou, Pingshan, Zhonghe – all evacuated within three days. The strategic city of Kaesong, defended by Kuroda Nagamasa’s Third and Sixth Divisions, fell almost comically when Kuroda, despite initial brave talk, set fire to the city and fled upon hearing exaggerated reports of approaching Ming forces.

Within twelve astonishing days, Li Rusong’s army had cleared northern Korea of Japanese troops, covering ground from Pyongyang to Kaesong and reclaiming twenty-two Korean districts. The Japanese withdrawal became a rout as survivors streamed south toward Seoul, where over 50,000 troops now concentrated for a final stand.

The Trap at Byeokjegwan

Flush with success, Li Rusong prepared to assault the Korean capital. However, Japanese commanders had learned from their defeats and devised a sophisticated trap. On January 26, 1593, Li dispatched a 3,000-man reconnaissance force under Zha Dashou toward Seoul. When this vanguard encountered what appeared to be a fleeing Japanese detachment, they pursued aggressively – exactly as the Japanese hoped.

The “retreating” Japanese led Zha’s troops into an ambush at Byeokjegwan, where over 20,000 Japanese soldiers lay concealed. By the time Zha realized his predicament, his force was completely surrounded. The subsequent battle saw some of the fiercest fighting of the entire war, as Zha’s outnumbered men fought desperately against waves of Japanese attacks.

Li Rusong, receiving reports of the engagement, personally led 2,000 cavalry to investigate. Dividing his force at Mashanguan, he advanced with just 1,000 men – a decision that likely saved his life. Arriving at Byeokjegwan, Li immediately recognized the gravity of the situation and, rather than retreating or digging in, made the bold choice to attack directly into the Japanese encirclement.

The Decisive Cavalry Charge

What followed demonstrated why the Liaodong cavalry remained the terror of East Asian battlefields. Li’s horsemen employed their three-eyed guns with devastating effect – firing three successive volleys before closing to melee range where they used the same weapons as iron clubs. Contemporary accounts describe Li Rusong fighting like a man possessed, cutting through Japanese ranks with his long saber despite being vastly outnumbered.

The battle reached its climax when a gaudily armored Japanese commander (possibly from the notoriously fierce Kyushu contingents) singled out Li for attack. Just as this warrior nearly overcame Li’s defenses, the commander’s younger brother Li Rumei fired a perfectly aimed arrow that struck the Japanese leader in the face, killing him instantly.

The arrival of Yang Yuan’s 1,000 reinforcements turned the tide completely. Mistaking these fresh troops for the vanguard of a larger Ming army, the Japanese broke and fled. When the dust settled, casualties stood at approximately 264 Ming dead against 167 Japanese – a remarkably even tally given the disparity in numbers.

Strategic Consequences and Legacy

Though tactically inconclusive, Byeokjegwan proved strategically decisive. Li Rusong recognized that frontal assaults against fortified Japanese positions would prove too costly given his limited manpower. Instead, he adopted Fabian tactics – avoiding direct confrontation while systematically destroying Japanese logistics. The bold raid on the Japanese grain depot at Ryongsan, which burned tens of thousands of tons of rice, proved particularly devastating.

By April 1593, Japanese forces abandoned Seoul and retreated to coastal strongholds at Busan and Ulsan. The first phase of the Imjin War ended with Japan’s invasion plans in ruins and over 35,000 casualties. Though fighting would resume in later years, the Japanese never regained the initiative lost during Li Rusong’s brilliant 1593 campaign.

Li himself would perish in 1598 during another frontier campaign, true to form while leading from the front. His legacy endures not just as a brilliant tactician, but as a poet-warrior whose verses captured the martial spirit of Ming China at its height. The Battle of Byeokjegwan stands as testament to his leadership – a moment when one commander’s courage and tactical brilliance altered the course of East Asian history.