The Nanboku-cho Period

In the mid Kamakura Period, the Imperial Family had two rival lines: the Daikakuji Line (daikakuji-to) and the Jimyoin Line (jimyoin-to).
Under a succession system set by the Kamakura Shogunate, emperors alternated between the two lines.
However, both believed their own line was the rightful one, and dissatisfaction with the rotation system grew.

Emperor Go-Daigo (Go-Daigo Tenno) of the Daikakuji Line sought to pass the throne to his descendants and moved to overthrow the Kamakura Shogunate.
He launched the Kenmu Restoration (Kenmu no Shinsei), aiming for an emperor-centered government without distinction between court nobles and warriors.
In reality, the warrior class tended to be treated less favorably than the nobility, and resentment toward Emperor Go-Daigo grew among the samurai who had carried out the overthrow.

Warlord Ashikaga Takauji and his younger brother Ashikaga Tadayoshi raised an army, and Emperor Go-Daigo was defeated in the Battle of Minatogawa.
The Kenmu Restoration ended after just two years. Ashikaga Takauji installed Emperor Komyo of the Jimyoin Line and founded the Muromachi Shogunate.

After the defeat at Minatogawa, Emperor Go-Daigo fled Kyoto for Yoshino in Nara.
Still asserting his legitimacy, he set the stage for a rare era with two emperors and two imperial courts:
,the “Southern Court” ruled by Emperor Go-Daigo of the Daikakuji Line
,the “Northern Court” ruled by Emperor Komyo of the Jimyoin Line, installed by Ashikaga Takauji

After installing an emperor of the Northern Court and founding the shogunate, Ashikaga Takauji came into conflict with his brother Ashikaga Tadayoshi.
Put at a disadvantage within the government, Tadayoshi sided with the Southern Court, the opposition to Takauji.

This clash undermined the lord-vassal order between the shogunate and samurai bands. Warriors increasingly acted to secure their own lands.
As a result, rivalries intensified to the point that alliances became unclear, and the conflict escalated into a large-scale struggle later known as the “Nanboku-cho Disturbance.”

To reunify the fragmented warriors, the Muromachi Shogunate appointed powerful samurai as shugo (military commanders and administrators) and dispatched them to the provinces.
As shugo authority expanded, they grew into figures with near-regional ruler power and became known as shugo daimyo.

Thanks in part to shogunate policies, the Muromachi Shogunate strengthened, and by the time Ashikaga Yoshimitsu became the third shogun, both the Southern and Northern Courts were weakening.
Although Yoshimitsu had become Minister of the Left within the Northern Court, he wanted more—his aim was to unify the two courts and place himself at the top.

After asserting its authority nationwide, the shogunate concluded the Meitoku Agreement with the Southern Court.
The agreement included:
,alternating imperial succession between the Daikakuji Line (Southern Court) and the Jimyoin Line (Northern Court)
,dividing imperial estates under set rules
,the Southern Court formally handing the Imperial Regalia (three sacred treasures passed down as symbols of the throne) to the Northern Court
It was favorable to the Southern Court, as it officially recognized the Southern Court’s legitimacy in the past.

However, the Northern Court was too weak to resist the shogunate and accepted the terms, leading to unification.
Afterward, Yoshimitsu persuaded the Southern Court side, and the emperor became a single Northern Court emperor.
Thus ended the Nanboku-cho conflict that had lasted for Approx. 60 years.

The Nanboku-cho Period saw instability unlike anything before.
Existing social structures stopped functioning, and not only the court and shogunate but ordinary people were also thrown into confusion.
In this climate, many turned to history for clarity. Works included Masukagami, which recounts about 150 years from the Genpei conflict from a court-noble perspective, and Jinno Shotoki, which explains the legitimacy of imperial succession from the Southern Court viewpoint using Shinto theory.

The Nanboku-cho Period also produced Taiheiki—famous to many Japanese today.
This war chronicle depicts the full scope of the Nanboku-cho conflict. It spread among the public through kōshaku (storytelling lectures) and had a major impact on later generations.
Earlier war tales were often performed by biwa-hoshi (lute priests), so its spread through kōshaku is one of Taiheiki’s defining features.

Mountain castle ruins in Takatori Town, central Nara Prefecture.
Its origins are said to date to the Nanboku-cho Period, when it was built by the local Ochi clan.
The elevation difference between the castle town at the foot and the honmaru (main enclosure) is 446 m—the largest height gap of any early modern Japanese castle.
It’s widely considered one of Japan’s great castles, designated a National Historic Site and selected as one of the Japan Castle Foundation’s Top 100 Japanese Castles.

A Shingon Buddhist temple said to have been founded in 859 by Prince Shinnyo (Shinnyo Hoshinno).
On the north side of the temple stands the Konpira-do, a hall enshrined outside the main precincts.
The temple preserves a kei, a percussion instrument struck during sutra chanting, dating back to the Nanboku-cho Period (14th century).