Mori Motonari (1497–1571), head of the powerful Mori clan, was one of the most influential daimyo in the Chugoku region, located in western Honshu. During the turbulent and violent Sengoku Jidai period, he waged continuous wars in an effort to expand his domain and strengthen his clan's power.
As early as 1543, Motonari had already attempted to seize Gassan-Toda Castle from his neighbor, Amago Haruhisa, but that attempt ended in failure. However, in 1561, Haruhisa died, and two years later, Motonari launched a new military campaign with the aim of conquering Izumo Province.
In order to isolate the enemy's main fortress, Motonari began to systematically capture the remote fortifications belonging to the Amago clan. Among them, the most significant was Shiraka Castle, the largest of the satellite castles (shijo), which was of key importance for defending the approaches to Gassan-Toda. In the fall of 1563, Motonari began his siege. The new head of the Amago clan, Yoshihisa, sent troops to help the besieged, but they were intercepted by Mori's army and defeated. The siege of Shirakawa lasted 70 days and ended in surrender after the besiegers managed to cut off the castle's water supply. The commander of the garrison, Matsuda Michihisa, chose to commit suicide rather than surrender to the enemy.
In the spring of 1564, Motonari approached the walls of Gassan-Toda. This citadel, which belonged to the Amago clan, was one of the five largest mountain castles of its time. Although Gassan-Toda was a yamajiro (mountain castle), it had a highly developed system of defensive structures. In addition to the traditional three courtyards—defensive lines located at the top of Mount Gassan—the fortress had other courtyards that descended in terraces down to the Toda River (now known as Iinashi) and its tributary.
The first attempt to storm the castle, protected by natural conditions and powerful fortifications, was unsuccessful. Mori's army suffered losses, and Motonari was forced to retreat to regroup his forces. In the summer of the same year, he returned to Gassan-Toda with an army of 25,000 samurai. At that time, the castle garrison numbered about 10,000 soldiers. This time, Motonari abandoned the idea of a direct assault and decided to wear down the fortress.
A long blockade began. Motonari issued an order not to accept defectors, thereby contributing to the rapid depletion of food supplies among the besieged. At the same time, he carried out a cunning political maneuver, using the well-known strategy of “killing with someone else's knife.” The head of the Amago clan, Yoshihisa, had a loyal vassal, Uyamahisakane, who was known as a skilled strategist and wise advisor. Motonaori, with the help of his agents, spread rumors among Yoshihisa's people that Hisakane was allegedly preparing to betray him. The false accusations achieved their goal — Yoshihisa believed them and ordered the execution of his valuable assistant. This act seriously undermined the morale of the castle's defenders.
Ultimately, when Motonari lifted the ban on accepting defectors, thousands of exhausted and half-starved Amago warriors abandoned their positions and fled the fortress. By the beginning of winter 1565, the situation inside the castle had become hopeless, and Yoshihisa decided to surrender. To the surprise of many of his contemporaries, Motonari showed mercy and spared the life of his defeated enemy. Yoshihisa was allowed to become a monk and go into exile at Enmyoji Temple in Aki Province.
See also
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The Siege of Tihaya Castle
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The Siege of Akasaka Fort
Kusunoki Masashige, hero of the Genko Rebellion (1331–1333), was a talented commander and inventive strategist. The two sieges of castles where he acted as defender are inscribed in gold letters in the history of Japanese military art.
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The Battle of Itinotani
After the death of Minamoto no Yoshinaka, the Genpei War entered its final phase, which is closely associated with the name of Minamoto no Yoshitsune. On March 13, 1184, he and his brother Noriyori set out to accomplish what their cousin had failed to do: deliver a final defeat to the Taira.
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The Battle of Uji 1180
Minamoto no Yorimasa did not need a special pretext for his growing hostility toward the Taira clan to turn into open rebellion. The court also included the discontented Prince Motohito, the second son of the former Emperor Go-Shirakawa. He had already been passed over twice in the selection of the heir to the throne. The second time this happened was in 1180, when the young Antoku was enthroned. Thus, Kiyomori, the head of the Taira clan, became the emperor's grandfather.
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The Battle of Shigisan
The conflict between the Soga and Mononobe clans, who were related to the imperial dynasty, arose on religious grounds. The Soga supported Buddhism, which had come from Korea, while the Mononobe remained faithful to Shintoism and fiercely opposed the spread of “foreign teachings.” Tensions reached a peak after the death of Emperor Yomei in 587.
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The Mongol invasion of Japan
At the end of the 13th century, Japan faced a danger far more serious than any internal strife. In 1271, the Yuan dynasty, founded by Kublai Khan, grandson of Genghis Khan, established itself in China. His army was truly enormous: tens of thousands of soldiers — Chinese, Koreans, Jurchen, and especially Mongols, who had conquered the territory from Korea to Poland and from the northern taiga to Egypt. Only one country remained unconquered — Japan.
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The Genpei War
As early as the 8th century AD, Japanese emperors gradually lost their real power and became symbolic figures, under the complete control of the powerful Fujiwara clan. This clan, by marrying their daughters to emperors, effectively monopolized the government of the country: all key military and administrative positions were held by representatives of the Fujiwara.
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The Rebellion of Fujiwara no Hirotsugu
Fujiwara no Hirotsugu was the son of Fujiwara no Umakai, one of the most important court officials of the Nara period. By 740, the Fujiwara clan had held the reins of government for several decades. However, in 735–737, Japan suffered a severe trial: the country was hit by a devastating smallpox epidemic. It coincided with a series of crop failures, and together, disease and famine claimed the lives of about 40% of the population of the Japanese islands. The consequences were particularly tragic for the aristocracy. The mortality rate among the court nobility exceeded that among the common people. All four Fujiwara brothers, who held the most important positions at court — Umakai, Maro, Mutimaro, and Fusasaki — died.
