[1339–1392] Nanboku-chō: War of the Northern and Southern Courts

The year is 1339. The dream of a restored imperial authority in Japan has died, and in its place, a nation finds itself torn in two. Less than a decade ago, Emperor Go-Daigo had briefly united the country under his rule in what was called the Kenmu Restoration. But that fragile peace was shattered by the very samurai warlord who helped him achieve it, the ambitious and brilliant Ashikaga Takauji. Now, two men claim the Chrysanthemum Throne. In the grand capital of Kyoto, the Ashikaga clan has installed their own emperor, a puppet ruler for their new military government, the shogunate. This is the Northern Court, residing in splendor, protected by the sharpest swords in the land. But far to the south, nestled in the misty, sacred mountains of Yoshino, the defiant Emperor Go-Daigo has established his own government in exile. This is the Southern Court, possessing the true Imperial Regalia—the sacred mirror, sword, and jewel—that bestows divine legitimacy. For the next fifty-seven years, Japan will bleed for the sake of two emperors, two courts, and two irreconcilable claims to a single throne.

Life in this divided land was a maelstrom of shifting loyalties. For the common farmer tilling their rice paddy, the ultimate authority was not some distant emperor, but the local samurai lord, the jitō, whose allegiance could change with the seasons. One year, your taxes and rice levy went to support the Northern Court’s armies; the next, a rival clan loyal to the south might sweep through, and the banners in the village would be forcibly changed. The constant warfare was a poison seeping into the soil. Armies marching across provinces would strip fields bare, commandeer supplies, and conscript able-bodied men, leaving villages vulnerable to famine and banditry. The air in the countryside was thick with uncertainty, the smell of woodsmoke from a distant skirmish a common and dreaded scent. This era gave rise to a powerful social phenomenon known as ‘gekokujō,’ a term meaning ‘the low overthrowing the high.’ Ambitious local warriors, seeing the chaos as an opportunity, rose up to challenge and displace their established masters, carving out their own domains in the turmoil. The old order was collapsing, and the sword was the only law that mattered.

In the north, Kyoto remained the heart of culture and power, but it was a heart with a warrior’s fist wrapped around it. Ashikaga Takauji and his successors began to build magnificent residences that blended the traditional airy styles of the court aristocracy with the more fortified, imposing features befitting a military ruler. While courtiers still dressed in elegant silk kimonos, the dominant fashion on the streets was that of the samurai. A warrior might be seen in a formal hitatare, a two-piece robe, when not clad in his fearsome suit of armor, or ‘yoroi,’ painstakingly crafted from hundreds of small, lacquered scales of leather and iron bound together by silk cords. Their primary weapons were the wickedly curved longbow, the ‘yumi,’ and the lethal ‘naginata,’ a long polearm with a curved blade that could cut down both infantry and cavalry. In contrast, the Southern Court in Yoshino was a rustic, desperate affair. Their ‘capital’ was a mountain fortress, their palaces little more than fortified temples. Their resources were meager, their existence a testament to sheer willpower and belief in their cause, fueled by the legendary loyalty of samurai houses like that of Kusunoki Masashige, who had died for Go-Daigo and whose sons carried on his fight.

The conflict was not a simple, clean war between two factions. It was a messy, brutal entanglement of personal ambition. Nowhere was this clearer than in the Kannō Disturbance, a civil war that erupted within the ruling Ashikaga clan itself between 1350 and 1352. Ashikaga Takauji, the shogun, came to blows with his own brother, Ashikaga Tadayoshi, a man who had been instrumental in running the shogunate’s administration. The feud became so bitter that at one point, Takauji’s brother and even his own son temporarily defected to the Southern Court, believing their cause to be the lesser of two evils. For a brief, intoxicating moment, the Southern Court’s armies, bolstered by these powerful defectors, managed to storm and capture Kyoto in 1352. For the loyalists who had fought for so long from their mountain exile, it must have felt like a miracle. But their triumph was short-lived. The Ashikaga were too powerful, their roots in the warrior class too deep. The Southern forces were soon driven back out of the capital, their hopes of a swift victory reduced to ashes.

Decades of relentless struggle slowly eroded the Southern Court's strength. Their geographical isolation in the mountains of Kii Peninsula made it difficult to gather resources and project power. While their claim to legitimacy was strong, legitimacy could not fill the bellies of soldiers or forge new swords. The Northern Court, backed by the Ashikaga shogunate, controlled the major economic centers, the fertile plains, and the levers of military production. As the years turned into decades, the cause began to seem hopeless. The fire of defiance that had burned so brightly under Go-Daigo was dwindling to embers as a new generation grew up knowing nothing but war.

By the late 14th century, a new shogun rose to power in Kyoto, Ashikaga Yoshimitsu. He was not merely a warrior, but a masterful politician and a patron of the arts who understood that the division was a persistent wound on the nation and a threat to the long-term stability of his family’s rule. He sought to end the conflict not with the sword, but with a promise. In 1392, he sent envoys to the weary Southern Emperor, Go-Kameyama, with a generous offer. If the Southern Court would end its resistance, return to Kyoto, and hand over the sacred Imperial Regalia, Yoshimitsu would ensure that the imperial line would henceforth alternate between the descendants of the northern and southern branches. It was a chance for peace and a promise that their line, and their sacrifice, would not be forgotten.

After fifty-seven years of bloodshed, the offer was too tempting to refuse. Emperor Go-Kameyama, his court depleted and his armies exhausted, agreed. He made the long journey from his mountain refuge to the glittering capital he had only known as an enemy stronghold. In a solemn ceremony, he formally abdicated and presented the sacred mirror, sword, and jewel to the Northern Emperor, Go-Komatsu. The war was over. The nation was, at last, united under a single emperor. But the peace was built upon a lie. The Ashikaga shogunate had no intention of honoring the agreement. The promise to alternate succession was broken. The imperial line of the Northern Court continued unbroken, while the Southern line was sidelined, its claim nullified, its long and bitter struggle ultimately rendered meaningless. The Nanboku-chō period had ended, leaving behind a unified nation under a powerful shogunate, but its foundation was a cynical betrayal that cemented the supremacy of the warrior class over the throne for centuries to come.