
Mori Tadamasa (1570 - July 31, 1634) was a notable military commander during Japan’s Warring States period and an early Edo-period daimyo. Initially, he governed Kawanakajima Domain in Shinano Province (modern-day Nagano Prefecture) and later became the first lord of Tsuyama Domain in Mimasaka Province (now northern Okayama Prefecture). He founded the Mori family line of the Ako Domain. Tadamasa’s family origins trace back to the Genji (Minamoto) clan, specifically the Kawachi-Genji branch from Kawachi Province (in present-day southeastern Osaka Prefecture), a lineage tied to Emperor Seiwa through his ancestor Yorisada Mori, a great-grandson of the famed Minamoto no Yoshiie.
In 1582, Tadamasa entered the service of Oda Nobunaga as a page but was soon dismissed after a scuffle with a fellow page, with Nobunaga deeming him too young for the position. This dismissal inadvertently spared Tadamasa from involvement in the Honno-ji Incident, where Nobunaga was assassinated. Two years later, in 1584, his older brother Nagayoshi was killed at the Battle of Komaki and Nagakute, and with his other brothers also deceased, Tadamasa inherited the Mori family estate. He was granted a 70,000-koku fief in Mino Province (southern Gifu Prefecture), residing at Kaneyama Castle. In 1587, Toyotomi Hideyoshi awarded him the surname Hashiba, and he was thereafter known as Hashiba Kaneyama Jiju (chamberlain).
During Hideyoshi’s Korean invasions, Tadamasa served as a public works administrator at Nagoya Castle in Kyushu, leading 2,000 troops. Following Hideyoshi’s death, Tadamasa allied with Tokugawa Ieyasu and received the Matsushiro Domain in Shinano Province (valued at 137,000 koku) in 1600. In the same year, he joined Tokugawa’s Hidetada Eastern Army at the Battle of Sekigahara, participating in the siege of Ueda Castle, home of Sanada Masayuki of the Western Army. Tadamasa resumed the Mori surname after the battle and was rewarded with the Tsuyama Domain (180,000 koku) for his service, becoming its first lord.
Tadamasa passed away in 1634, reportedly after developing severe stomach pain following the consumption of a peach, likely due to food poisoning. He was interred at Sangen-in, a sub-temple of Daitoku-ji in Kyoto’s Murasakino, which is also associated with the family of Ishida Mitsunari.
See also
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Asakura Yoshikage

Yoshikage was the eldest son of Asakura Takakage. He began ruling in 1548 at the age of fifteen, and during his reign he twice defeated the Ikko-ikki forces, in 1555 and 1564. Yoshikage supported the Saito family in their struggle against Oda Nobunaga in 1561–1567. When Ashikaga Yoshiaki fled Kyoto in 1565 after the assassination of his older brother, Shogun Ashikaga Yoshiteru, Yoshikage gave him refuge. However, he was unable to provide sufficient support for Yoshiaki's claim to the title of shogun, and Yoshiaki had to seek help from Oda Nobunaga.
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Asakura Norikage

Norikage came from the ancient samurai clan of Asakura, whose members considered themselves descendants of Prince Kusakabe, son of Emperor Tenmu (631–686). He was the eighth son of daimyo Asakura Takakage and was named Kotaro in childhood. Over time, Asakura Norikage became the pillar of the Asakura clan and was undoubtedly its most talented commander during that difficult period when the clan was experiencing internal difficulties, uprisings by the Ikko-ikki sect, and instability in the lands surrounding the capital. Although Norikage himself was never a daimyo, he served as an advisor to three generations of Asakura clan leaders. He spent his entire life on military campaigns. After his father's death in 1481, Norikage entered the service of his brother, Asakura Ujikage.
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Asai (Azai) Nagamasa

Asai Nagamasa inherited power from his father, Asai Hisamasa, when he was only fifteen years old. Both brave and impulsive, he proved himself a capable commander, managing to regain lands from the Rokkaku clan that had previously been lost by his father. After a territorial dispute with Oda Nobunaga over the province of Mino, Nagamasa formed an alliance with Nobunaga and married his sister Oichi, who was famous for her beauty. In 1570, when Oda Nobunaga declared war on the Asakura family, Nagamasa sided with the Asakura because he had long-standing ties with them. This unexpected move threatened Nobunaga's invasion of the Asakura lands by threatening him from the rear. Oda managed to save his army, not without the help of Tokugawa Ieyasu, but relations between Nobunaga and Asai were permanently damaged.
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Amano Yasukage

Yasukage was born into the family of the samurai Amano Kagetaka and was given the name Matagoro at birth. He later changed his name to Kageyoshi, and then to Yasukage. From an early age, Yasukage served Tokugawa Ieyasu and accompanied him when he was held hostage by Imagawa Yoshimoto. His loyalty and devotion to Ieyasu from a young age laid the foundation for Yasukage's future military and administrative career.
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Amago Tsunekisa

The Amago clan (also spelled Amako) was founded in 1392, when Sasaki Takahisa, who was orphaned at the age of three, took the new surname Amago, meaning “son of a nun,” in honor of the nun who raised him. Since the Sasaki family descended from Emperor Uda (866–931), the Amago clan traced its lineage back to this emperor. From around 1396, the Amago clan's headquarters was the mountain castle of Gassan-Toda in Izumo Province. Until the start of the Onin War, the Amago clan remained a minor clan in the service of the Kyogoku clan, which was also a descendant of the Sasaki clan. The Amago clan historically held the position of vice-governor of Izumo Province.
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Abe Masakatsu

Masakatsu came from the ancient Abe clan, whose progenitor, according to the Nihon Shoki chronicle, is considered to be Prince Ohiko-no-mikoto (2nd century BC), son of Emperor Kogen. From the Nara period (710–784), members of the Abe clan held high positions in the government, including at the ministerial level, and from the Heian period (794–1185) onwards, the clan gained widespread fame, which continued until the Edo period.
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Toyotomi Hidenaga
Toyotomi Hidenaga was an outstanding military commander and strategist of his time, who was unjustly overshadowed by his half-brother, the great Toyotomi Hideyoshi. At different stages of his life, he was known by the names Kinoshita Koichiro, Hashiba Nagahide, and Hashiba. Despite his relative obscurity among the general public, Hidenaga was considered one of the best minds of his time, on par with the renowned Kuroda Kanbei.
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Matsudaira Nagachika

Matsudaira Nagachika (1473–1544?) was a daimyō of Japan’s Sengoku period and the third son of Matsudaira Chikatada. He was also the great-grandfather of Tokugawa Ieyasu.
