December 5, 1937 - Chinese Defenses Collapse as Japanese Forces Enter Nanjing

By December 5, 1937, Japanese forces were closing fast on Nanjing after capturing Shanghai and racing inland at up to 40 kilometers per day. Chinese defenses were already stretched thin from months of brutal fighting, leaving roughly 100,000 largely untrained troops to hold the capital. Command was fractured, logistics had collapsed, and morale was crumbling. The city's fate was essentially sealed before a single Japanese soldier reached its walls — and what followed was far worse.

Key Takeaways

• Japanese forces did not enter Nanjing on December 5; they reached its outer walls at dawn on December 9, 1937.
• Chinese defenses at the Fukuo Line held until December 9, when two days of heavy fighting finally breached fortifications.
• Subordinate Japanese commanders advanced at speeds up to 40 kilometers daily, outpacing General Matsui's planned slow march toward Nanjing.
• Chiang Kai-shek issued retreat authorization on December 11, but Tang Shengzhi delayed execution while seeking a last-minute ceasefire.
• Four Japanese divisions stormed Nanjing before dawn on December 13, entering through multiple gates after a four-day battle.

Japan's Rapid March on Nanjing After Shanghai's Fall

With Shanghai secured in November 1937, Japanese forces wasted no time launching their rapid advance toward Nanjing, China's capital. Moving at breakneck speeds of up to 40 kilometers per day, subordinate commanders actively disobeyed General Matsui's plan for a slow, steady march, racing each other toward the city instead.

This aggressive pace created serious logistics strain, forcing troops to carry minimal supplies beyond weapons and ammunition. To compensate, Japanese soldiers looted civilians along the route, accompanying their raids with extreme violence and terror campaigns that functioned as brutal propaganda campaigns, crushing any remaining Chinese will to resist.

Cities fell rapidly. Danyang capitulated on December 2, more than five days ahead of schedule, while Suzhou's fall left approximately 1,000 Chinese soldiers dead and 100 artillery pieces captured. The entire advance from Shanghai to Nanjing unfolded over just five weeks, with Japanese forces completing their march by December 9. The atrocities committed during this advance fit a broader pattern of Japanese violence along the Lower Yangtze River, beginning with the Battle of Shanghai.

How China's Defense Lines Crumbled in December 1937

By December 9, Japanese forces had reached the Fukuo Line—China's final defensive barrier before Nanjing's walls. After two days of intense fighting, Japanese artillery and infantry overwhelmed the fortified positions, exposing Nanjing directly to assault.

Chiang Kai-shek ordered retreat at noon on December 11, but commander Tang Shengzhi delayed execution, attempting a last-minute ceasefire through German mediators. That hesitation proved catastrophic.

Logistical failures and morale collapse shattered any coordinated withdrawal, turning Tang's breakout order into a chaotic rout. Most units disintegrated rather than retreating effectively. This outcome was foreshadowed by China's longstanding policy of "first internal pacification," which had diverted critical resources and military preparedness away from confronting Japanese aggression for years.

The fall of Nanjing marked the culmination of a broader Japanese campaign that had begun with the Battle of Shanghai, where over three months of brutal urban warfare, amphibious landings, and flanking maneuvers had systematically dismantled Chinese defensive positions and forced a costly retreat toward the capital.

The Four-Day Battle That Broke Nanjing's Walls

Dawn on December 9 brought Japanese infantry to Nanjing's outer walls, opening a four-day battle that would seal the city's fate.

You'd watch the 36th Infantry Regiment hammer defenders near Guanghua Gate until Chinese troops, having taken 50% casualties, fell back behind the walls.

Frustrated by the stalemate, Japanese commanders redirected their artillery logistics toward Zhonghua Gate on December 11, while aircraft routed Chinese forces outside the walls. Japanese mountain guns destroyed part of Guanghua Gate by nightfall, overwhelming the remaining defenders and breaching the city's outer fortifications.

Before Nanjing's walls were ever tested, Chinese forces had already endured brutal Japanese aggression in Shanghai, where the Eight Hundred Heroes held Sihang Warehouse for four days against aircraft, tanks, and artillery before the city fell in late October 1937. Much like the Tour de France's 1904 edition, which nearly collapsed under widespread cheating before organizers tightened monitoring and verification to preserve the event's integrity, Nanjing's defenders faced a crisis that exposed the limits of their ability to sustain organized resistance.

Why Did General Tang Sheng-chi Order the Retreat?

As Japanese forces pressed against Nanjing's walls, General Tang Sheng-chi found himself trapped between an impossible military reality and Chiang Kai-shek's political calculations.

Chiang prioritized political optics over survival, ordering Tang to hold long enough for public perception. Tang knew the truth and acted accordingly:

1. He gathered divisional commanders and showed them Chiang's retreat authorization
2. All commanders signed a document sharing command responsibility
3. Tang attempted a last-minute ceasefire through German mediators Rabe and Sperling
4. On December 12, he ordered the general retreat and fled through Yijiang Gate

You can see Chiang's fingerprints everywhere. He issued contradictory orders, telegraphed retreat permission only when collapse was inevitable, then let Tang absorb the blame for losing China's capital. Tang's garrison was severely weakened from the start, as the roughly 100,000 soldiers he commanded were mostly untrained and included defeated troops from Shanghai.

Before the ground invasion even began, the city had already endured days of relentless aerial bombing in early December, further eroding both infrastructure and troop morale ahead of the final collapse.

How Chiang Kai-shek's Withdrawal Order Left Nanjing's Troops Behind

Chiang Kai-shek's withdrawal order didn't save Nanjing's defenders — it abandoned them. When Chiang telegraphed Tang Shengzhi on December 11, authorizing retreat "if necessary," the vague wording triggered command failures that proved fatal.

Tang demanded Chiang's personal confirmation before acting, delaying any organized evacuation. Meanwhile, contradictory instructions left subordinate commanders torn between defending to the death and withdrawing.

Chiang's culpability runs deeper than poor timing. He'd already evacuated Nanjing by December 7, prioritizing his own safety while 100,000 troops awaited clear orders.

When the retreat finally began on December 12, it collapsed into chaos. Soldiers couldn't escape Japanese encirclement, leaving thousands stranded inside the city. By December 13, those abandoned men faced Japanese forces that showed no mercy — and the massacre began. The violence that followed lasted six weeks, resulting in the deaths of up to 300,000 Chinese civilians and disarmed soldiers.

The broader campaign along the upper Yangtze that preceded Nanjing's fall had already devastated Chinese fighting capacity, with Chinese forces suffering over 200,000 casualties at Shanghai alone before the retreat toward Nanjing ever began.

Soldiers in Civilian Clothes and the Breakdown Inside Nanjing

When Japanese forces entered Nanjing on December 13, they didn't just hunt soldiers — they hunted anyone who looked like one. Civilian disguises couldn't protect innocent men from arbitrary suspicion. Healthy males became automatic targets during refugee searches lasting three weeks inside the Safety Zone.

Japanese troops flagged and killed:

1. Rickshaw coolies and laborers pulled from streets without evidence
2. Buddhist burial workers from the Red Swastika Society marched away and executed
3. Chinese police and firefighters misidentified as disguised combatants
4. Carpenters and street sweepers swept up during military operations

You'd have no way to prove your innocence. Fleeing meant being shot on sight. Staying meant risking execution anyway. The breakdown inside Nanjing left ordinary civilians with no safe choice. China estimates 300,000 people dead at Nanjing alone, a toll that has shaped national memory and fueled decades of unresolved grief toward Japan. Decades later, two men wearing World War II-era Japanese uniforms and posing cheerfully near Nanjing fortresses sparked outrage so severe that the city's massacre memorial condemned the images as a shocking affront to national memory.

The Last-Minute Ceasefire Attempt Before Nanjing Fell

With Nanjing's defenses crumbling and Japanese forces closing in, Tang Sheng-chi made a frantic last-minute bid for a ceasefire on December 12, 1937. Startled by the relentless Japanese onslaught, he turned to foreign intermediaries John Rabe and Eduard Sperling, both German citizens operating within the city, to apply diplomatic pressure on Japanese commanders.

Rabe, already chairing the Nanking International Safety Zone Committee, had previously boarded the USS Panay to seek Chiang Kai-shek's approval for negotiations. Despite these efforts, the Japanese refused to halt their bombardment of Zhonghua Gate.

The ceasefire bid collapsed without any agreement, leaving the Chinese garrison to face overwhelming artillery and aerial bombardment through the night, sealing Nanjing's fate by December 13. Matsui Iwane, commanding general of the Japanese Central China Front Army, had ordered the destruction of Nanjing, and he would later be tried and executed for war crimes by the International Military Tribunal for the Far East. The events of this period are today examined in educational curricula, where survivor testimony is used to confront the full enormity of the crimes committed during the fall of Nanjing.

Japanese Forces Enter Nanjing on December 13, 1937

Before dawn broke on December 13, 1937, four Japanese divisions stormed Nanjing simultaneously, entering through multiple gates while the city's defenses had already crumbled overnight.

Urban combat swept through every district as civilian evacuation became impossible.

Here's what unfolded within hours:

1. 6th and 114th Divisions advanced from the south, seizing Zhonghua Gate
2. 9th Division broke through Guanghua Gate after Chinese defenders suffered 50% casualties
3. 16th Division captured Zhongshan and Taiping Gates using artillery from Zijinshan
4. Japanese Navy fleets secured both Yangtze riverbanks, cutting off escape routes

What followed the city's fall would become one of history's darkest chapters, as large-scale massacres of prisoners of war and indiscriminate killing of unarmed civilians began almost immediately after occupation.

How the Safety Zone Became a Japanese Target

Although Japanese authorities had promised to respect the Safety Zone if it remained free of Chinese troops, they disregarded its boundaries from December 14, 1937, entering under the pretext of hunting soldiers. These Japanese violations escalated quickly — troops burned shelters, looted buildings, and raped refugees within the zone's boundaries.

The massive refugee influx had also made the zone a political obstacle, effectively crippling Japan's puppet regime. By February 1938, Japan ordered refugee expulsions, prohibiting commercial activity and threatening forcible eviction if refugees hadn't returned home by February 4.

The International Committee, lacking sufficient resources, couldn't fully prevent these abuses. On February 18, 1938, Japan dissolved the Safety Zone entirely, reorganizing it into the Nanking International Relief Committee, ending its role as a civilian sanctuary. At its peak, the zone sheltered nearly 70,000 refugees by December 21, 1937, across 26 committee-managed shelters struggling to maintain basic necessities.

The Safety Zone Committee worked to hold Japanese forces accountable by fastidiously documenting misconduct, sending daily letters of protest to the Japanese embassy in Nanjing and international organizations detailing mass violence and rape, with compiled firsthand accounts later published in newspapers and journals across the United States and Europe.

The Nanjing Massacre: Mass Killings, Rape, and the Death Toll

Once Japanese forces secured Nanjing on December 13, 1937, they unleashed a campaign of mass killings, rape, and systematic destruction that lasted through March 1938. Civilian testimonies reveal the horrifying scope of what unfolded:

1. Mass Executions – The IJA killed between 29,000 and 200,000+ victims, dumping bodies into the Yangtze River or burying them in mass graves.
2. Rape Epidemic – Soldiers committed an estimated 20,000 rapes, targeting women aged 8 to elderly.
3. Mopping Up Operations – 20,000 civilian men were falsely labeled soldiers and executed.
4. Memorial Preservation – Death toll estimates range from 40,000 to 300,000, making accurate historical documentation critical. The Nanjing War Crimes Tribunal recorded estimates reaching as high as 430,000 victims, reflecting the deeply contested nature of the historical record.

You can't separate truth from tragedy without preserving these records.