Lifespan: Tenbun 16 (1547) to 6/5 of Tenshō 15 (1587)
Other Names: Matashichirō (childhood), Nakatsukasa-taifu (informal), Chūsho (informal)
Lord: Shimazu Takahisa → Shimazu Yoshihisa
Father: Shimazu Takahisa
Mother: Daughter of Honda Chikayasu
Siblings: Yoshihisa, Yoshihiro, Toshihisa, Iehisa
Wife: [Formal] Daughter of Kabayama Yoshihisa
Children: Toyohisa, Tadanao, daughter (wife of Nejime Shigehira), daughter (wife of Sata Hisayoshi), Sōtetsu (wife of Shimazu Hisanobu, wife of Sagara Yoriyasu)
Shimazu Iehisa served as a bushō during the Sengoku and Azuchi-Momoyama periods. He was a retainer of the Shimazu clan of Satsuma Province and served as the chamberlain of Sadowara Castle in Hyūga Province.
In 1547, Iehisa was born as the fourth son of Shimazu Takahisa, a sengoku daimyō and the fifteenth head of the Shimazu clan. From an early age, he was assessed by his grandfather, Shimazu Tadayoshi, as having acquired skills in the military arts. In the seventh month of 1561, his first experience in battle occurred at Mawarizaka against the Kimotsuki clan of Ōsumi Province. Despite being only fifteen years old, he killed an opposing commander, Kudō Oki-no-kami, in a clash of spears.
In a conflict against members of the Hishikari clan holed-up in Ōkuchi Castle and reinforcements from the Sagara clan, on 5/8 of Eiroku 12 (1569), Iehisa had Ōno Tadamune and Miyahara Kagetane lead troops to set-up ambushes on Tokami-ga-o and Mount Inari while Iehisa himself led 300 soldiers through the rain disguised as a supply battalion to pass-through a road in the foothills of Ōkuchi Castle. This induced soldiers from the castle to approach who were then caught in the ambushes. A total of 136 enemy troops were killed.
In 1575, Iehisa traveled to Kyōto to worship at the Ise Shrine for the divine protection of the gods in the course of the pacification by the Shimazu clan of three provinces. Iehisa recorded the details of this journey to the capital in a daily journal. During the trip, he spent one evening in the village of Ao in Iga Province. In the fourth month, he stayed at the residence of Shinzen, a disciple of Satomura Jōha, a master of renga, or linked-verse poetry. While in the capital, through introductions by Jōha, Iehisa had exchanges with local nobility as well as merchants from Sakai. With Shinzen serving as his guide, Iehisa observed a huge army led by Oda Nobunaga with several tens of thousands of soldiers from seventeen provinces returning from an assault against the Hongan Temple in Ōsaka. He said that Nobunaga was dozing while atop a horse. In the fifth month, with Akechi Mitsuhide acting as his guide, Ieyasu visited Sakamoto Castle in Ōmi Province. He was deeply impressed by the level of preparedness to hold the castle. Thereafter, he visited Tamonyama Castle and enjoyed other splendid sights in Yamato Province. Later, the chamberlain named Yamaoka Kagesuke offered him a small evergreen tree known as wax myrtle and he was entertained with saké.
During these travels, Iehisa visited many castles and recorded his impressions of Mitsuodake Castle in Suō Province and Ikeda Castle in Settsu Province.
Battle of Okitanawate
After the Battle of Mimikawa in 1578, the Ōtomo clan of Bungo Province declined while Ryūzōji Takanobu of Hizen Province rose to prominence. This led to a contest between the Shimazu and Ryūzōji clans for the domination of Kyūshū. In battles between the two parties in the direction of Chikugo and Higo provinces, the Ryūzōji frequently overwhelmed the Shimazu forces. In the western portion of Hizen, however, Arima Harunobu plotted to abandon the Ryūzōji and requested reinforcements from the Shimazu, creating favorable circumstances for the Shimazu to gain ground against their rival.
In the third month of 1584, the Shimazu army came to the support of the Arima clan and, in an effort to intercept the Ryūzōji forces, headed toward Shimabara with Ieyasu serving as the commander-in-chief. After converging with the forces led by Arima Harunobu, the combined army totaled between 5,000 and 8,000 soldiers, whereas the Ryūzōji fielded from 18,000 to as many as 60,000 troops. Based on the historical records, the number of soldiers in each army varies. In an event known as the Battle of Okitanawate, Iehisa lured the Ryūzōji army into a narrow wetlands area called Okitanawate. he then deployed a secret tactic conceived by the Shimazu army known as tsurinobuse by which the Shimazu would draw-out the enemy and then attack from the flanks with arrows and arquebus fire. This caused the Ryūzōji to fall into dissarray while their commander-in-chief, Takanobu, along with many members of the family as well as senior retainers were killed.
Owing to this victory, there were no daimyō remaining in Kyūshū who could effectively oppose the Shimazu clan. In recognition of this achievement, Iehisa was awarded a fief of 4,000 koku and elevated beyond the status of an individual living in a single room. Iehisa became the chamberlain of Sadowara Castle and was assigned responsibility for managing affairs in Hyūga Province. Thereafter, Chikugo Province became the main site of battles while Shimazu forces in Higo Province aimed to march north. Takanobu’s younger brother-in-law, Nabeshima Naoshige, expressed a desire to resist to the end, refusing to accept Takanobu’s head sent to him by the Shimazu. Consequently, for the time being, the Shimazu forces withdrew. Nevertheless, as the Shimazu clan continued to gain power, the Ryūzōji entered into a settlement analogous to surrender as a means to preserve their own sphere of influence. Meanwhile, Naoshige secretly communicated with Toyotomi Hideyoshi and, in 1587, during the Subjugation of Kyūshū by the Toyotomi army, Naoshige served in the vanguard of the Ryūzōji and Nabeshima forces to subdue the Shimazu.
Battles against the Toyotomi
In pursuit of their goal to control Kyūshū, the Shimazu attempted to attack the Ōtomo clan of Bungo, but, after the Ōtomo met with Hideyoshi in Kyōto, in 1586, a vanguard division of 6,000 soldiers in the Toyotomi allied army led by Sengoku Hidehisa, along with Chōsokabe Motochika and Chōsokabe Nobuchika (father and son), Sogō Masayasu, and others, landed in support of the Ōtomo for a campaign known as the Subjugation of Kyūshū. Iehisa led forces to intercept them, resulting in the deaths of over 4,000 soldiers in total on both sides of the violent battle. During the collapse of the Toyotomi allied army, Nobuchika and Masayasu were killed in action and the Shimazu prevailed. This event is known as the Battle of Hetsugigawa.
Thereafter, on the condition of a fief in the vicinity of Kyōto, prior to the surrender of Shimazu Yoshihisa and Shimazu Yoshihiro, Iehisa was the first of four brothers to individually settle with the army of Toyotomi Hidenaga. Then, on 6/5 of Tenshō 15 (1587), he suddenly died at Sadowara Castle. His cause of death is uncertain and the subject of various theories including that he died of illness or that he was poisoned by the Toyotomi or the Shimazu. Owing to the lack of compelling reasons for the Toyotomi or Shimazu to poison him, and based on a letter dated 5/13 of the same year from a close associate of Hidenaga named Fukuchi Nagamichi to Yoshihiro stating that Iehisa died of illness, this is the generally accepted theory. He was forty-one years old.
Luís Fróis, a Jesuit missionary from Portugal who resided in Japan during the Sengoku period, noted in his chronicles that Iehisa was an extraordinary bushō – an experienced veteran with a courageous spirit.
He was said to have been distant from the cultural arts. While traveling to Kyōto, when Akechi Mitsuhide offered him tea, he noted that he was not familiar with the tea ceremony so he only desired boiled water. At this time, he was also invited to a renga event, but declined.
After the Battle of Okinawate, there are misunderstandings that he was awarded landholdings of 30,000 koku in Sadowara. This did not occur until later during the establishment of the Sadowara domain headed by Shimazu Mochihisa. During the period after the Battle of Okinawate, the order of status in the Shimazu family was Yoshihisa, Yoshihiro, Yoshitora (of the Sasshū branch), and Toshihisa. Iehisa was not at such a high rank. The descendants of Shimazu Tadanao (Iehisa’s second son), the only family members remaining from his direct lineage, appeared to have refrained from using the Shimazu surname.
In 1586, after the Battle of Hetsugigawa, Iehisa dispatched a retainer named Kawakami Hisatomo to meet Chōsokabe Motochika (who could not depart to his base in Tosa Province by ship owing to a low tide), and to communicate that the killing of Nobuchika was an unavoidable event on the battlefield and that he should gradually draw-down his camp by high tide.
Iehisa did not have a child by his formal wife, but, instead, by a consort who was not of high social status.
One incident occurred when Iehisa and his brothers were loading horses with provisions in Yoshino in Kagoshima. After finishing the work, while looking at a yearling, Toshihisa turned to Yoshihisa and Yoshihiro and said: “As I look at several horses, I see that the color of their hair usually resembles their mother. I think that’s the same for people.” Yoshihisa understood what Toshihisa was trying to say, and said: “Some people resemble their mothers, but you cannot say that as a rule. Some horses resemble their fathers and, even though it can be said that people are the same, given that people are not beasts and have the virtue of a heart. If one studies and raises his virtues, he may surpass unworthy parents and, if one is estranged from virtue, he will be inferior to his parents.” Thereafter, Iehisa dedicated himself day and night to studying and learning the military arts. He did not waste any of his time and, within several years, cultivated superior knowledge of these subjects, eliminating any gap relative to the skills of his brothers.
Kabayama Tadasuke, the older brother of Iehisa’s wife, noted in his diary that it was improper behavior for Shimazu Yoshihiro, as a commander-in-chief, to be jealous of the military achievements of Iehisa. This reflected the delicate position of Iehisa among his brothers who, in addition to sparking envy based on his meritorious service, was born to a different mother than the others.
Yoshihisa, Yoshihiro, and Toshihisa were born to a different mother. Iehisa’s mother was the daughter of Kabayama Yoshihisa. Yoshihisa also conveyed the kokin denju to Iehisa. (Tō Tsuneyori is known as the forefather of the kokin denju, interpretations of waka, or classical Japanese poetry, communicated in the form of historical secrets from instructors to their disciples.)
His eldest son, Shimazu Toyohisa, met a valorous end while serving in the rear guard during the withdrawal of the Western Army at the Battle of Sekigahara in the ninth month of 1600. His second son, Shimizu Tadanao, was sent for adoption by the Tōgō clan (an illegitimate branch of the Shibuya clan of Sagami Province). His second daughter wed Sata Hisayoshi of the Sata clan, an illegitimate branch of the Shimazu, and his third daughter wed Sagara Yoriyasu, the son of Indō Yorimori, a chief retainer of the Sagara clan. Shimazu Tadatsune, the third son of Yoshihiro and first lord of the Satsuma domain, later received one of the characters from the name of Tokugawa Ieyasu and adopted the same name of Iehisa, but he was a nephew.