Diary insights into the Shimazu

Shimazu Yoshihisa, one of the ten most famous Samurai warriors in history, was born 490 years ago today. He went far towards uniting all the clans on the island of Kyūshū but was eventually defeated by Toyotomi Hideyoshi who, later, succeeded in unifying Japan. A key source of information about Yoshihisa and the workings of the Shimazu clan is the diary of one of Yoshihisa’s close advisers, Uwai Kakuken.

Yoshihisa was born on 9 February 1533, the eldest son of the chief of the Shimazu clan of Satsuma province. According to Wikipedia, he took the name of Tadayoshi but after receiving a kanji from the shōgun he changed it to Yoshitatsu, and later Yoshihisa. He married his own aunt and after her death, married his relative, a daughter of Tanegashima Tokitaka. In 1566, he succeeded his father as the head of Shimazu clan, becoming the clan’s sixteenth leader. 

Working together with his brothers, Yoshihisa launched a campaign to unify Kyūshū (the third-largest island of Japan’s five main islands). Starting in 1572 with a victory against Itō clan at the battle of Kizaki and the Siege of Takabaru in 1576, Yoshihisa continued to win a series of battles. By the mid-1580s, he had amassed, it is said, an army of over 100,000, and had conquered almost all of the island.

However, the Ōtomo clan, controlling the last unconquered area, sought and eventually won help from Toyotomi Hideyoshi, now called the second ‘great unifier’ of Japan. By mid-1587, Yoshihisa’s forces were overwhelmed. Towards the end of the year, he called for a truce, which Hideyoshi eventually agreed to.  Most of lands conquered by the Shimazu clan went to followers of Hideyoshi, but the Shimazu held on to the Satsuma and Ōsumi rovinces, as well as half of Hyuga. Yoshihisa shaved his head to show he would become a Buddhist monk if his life was spared, but, it is believed, he continued to wield power through his younger brother Yoshihiro. Yoshihisa died in 1611. According to TopList, he is one of the ten most famous Samurai warriors in history.

There is no evidence that Yoshihisa kept a diary, but a contemporary of his, Uwai Kakuken, also a Samurai in the Shimazu clan, and an adviser to Yoshihisa, did keep a diary. Uwai was born in 1545, had his first military engagement in 1561, and was named Chief Retainer (i.e. a trusted individual who defended the leader’s castle while he was away at battle) in 1576. He suffered a serious injury in 1586, and subsequently submitted to Hideyoshi’s authority, relinquishing the castle to him, and taking up retirement at Ijūin in Satsuma province. He died in 1589. However, parts of a diary he kept survived and are an important first hand source of information about the Shimazu.

Indeed, a student at the University of Michigan, Vincent Chan has used the diary extensively for his Doctor of Philosophy dissertation entitled Running the Domain: Truth, Rumours, and the Decision-Making of the Shimazu Warrior Family in 16th Century Japan. The abstract begins: ‘Using the Uwai Kakuken nikki, a diary kept by the middle-ranking warrior Uwai Kakuken from 1574 to 1586, this dissertation examines some fundamental factors that contributed to the political decision-making process of the Shimazu family in late sixteenth century Japan.’

Throughout the dissertation, Chan provides quotes (translated into English) from the Uwai Kakuken nikki. Evidently, though, this is an academic thesis and quite arcane in parts. Here is a sample of Chan’s analysis (one which refers directly to Yoshihisa).

‘In examining the effects that rumours had on the political decisions of the Shimazu, the case of the Iriki-in and the rumours surrounding their ambitious plan to betray Yoshihisa illustrates for us how rumours can be used by the daimyo for his personal gains. Specifically, Yoshihisa used the Iriki-in rumours to reinforce his own authority within the Shimazu family and protect his image as a filial son. This case also highlights the fact that there were no attempts to investigate the validity of the rumours, nor were there any attempts to find their origins. This was consistent with the way rumours were treated throughout the medieval era. Instead, the burden of proof to show the innocence of the Iriki-in fell on the shoulders of Iriki-in Shigetoyo (d. 1583), the leader of the Iriki-in family at the time of the incident. Yoshihisa’s decision to force Shigetoyo to do everything he can to disprove the rumours, allowed Yoshihisa to achieve two primary objectives. First, Yoshihisa was able to seize control of some of the key Iriki-in landholdings on legitimate grounds, thus reinforcing his political legitimacy as the ruler of the Shimazu. Second, Yoshihisa managed to reinforce his reputation as a daimyo who exercised his power in a measured manner by allowing Shigetoyo to take the initiative in proving his innocence. Let us begin by looking at the circumstances that these rumours appeared in the historical records.

We get a sense of the tension between Iriki-in Shigetoyo and Shimazu Yoshihisa from the opening passages of Kakuken’s diary. On the first day of the eighth month of Tenshō 2 (1574), Kakuken wrote,

Item. This morning it was stated that the sword from Iriki-in (Shigetoyo) should be given to our lord as a gift after the presentation of the gift from Tōgō (Shigehisa). The senior retainers stated in response, “Since Tōgō, Kedō-in, and Iriki all stemmed from the same family, it should be Nejime (Nejime Shigenaga) who presents his sword as a gift next.”

The mediator from Iriki (Satsuma district, Iriki-in Shigetoyo), Murao Kurando said, “As I am still inexperience in such matters, I must first return to Danjō-no-chū (Shigetoyo) and ask him for his orders. A decision should be made soon.”

The senior retainers reconsidered this and replied, “If one person from that family was prioritized before others, it should not matter when the other branch families present their gifts.” Despite this, the mediator retired from court without understanding the senior retainers’ position nor providing a response. The go-between for this situation was Honda (Chikaharu) Inaba-no-kami and myself.

As this was the first entry of Kakuken’s diary, we were given no context of the underlying tension between the Shimazu and the Iriki-in present at this time.

A brief outline of what was supposed to happen on this specific day can be seen through Kakuken’s actions during this event. The first of the eighth month was hassaku, a day for lord and vassal to exchange gifts to reaffirm their bonds. On this particular day, the many other retainers of the Shimazu were set to present their daimyo with gifts as part of a ritualistic gift exchange. For example, Kakuken presented Yoshihisa with a single sword and a hundred copper coins. In return for these gifts, Yoshihisa awarded Kakuken with a sword and a bow. There was an underlying political purpose here. With the exchange of gifts, the relationship between a lord and his retainers was supposedly reaffirmed. As this relationship formed the basis of political power and authority during the Sengoku period, we can easily see why participation in this act of gift exchange might be important for retainers and daimyo alike.’