Letter From Hideyoshi to Hidenaga Discovered
New Information Revealed, Joking Report Made
According to a report in the Yomiuri Newspaper dated Friday September 20, a letter from Toyotomi Hideyoshi to his younger brother Hashiba Hidenaga, jokingly reporting on the 1584 Battle of Komaki and Nagakute, has been discovered at a museum in Suzaka, Nagano.
Battle
Two years after the death of Oda Nobunaga, Toyotomi Hideyoshi had basically usurped Nobunaga’s power and domains, and shunted Nobunaga’s surviving second and third sons out of the scene. The indignant second son of Nobunaga, Oda Nobukatsu had refused an invitation to the opening of Hideyoshi’s grand Osaka Castle, thinking it would simply be kowtowing to his father’s former vassal. Hideyoshi is said to have reached out to Nobukatsu’s generals to smooth the matter over, but rumors arose, and Nobukatsu had the three generals executed for treachery. This gave Hideyoshi an excuse to destroy Nobukatsu, and so approximately 80,000 Toyotomi troops entered the Owari districts.
Nobukatsu, heavily outnumbered, sought the support of Tokugawa Ieyasu, and when the 35,000 Tokugawa and Oda allied forces arrived at Komaki, it soon became a battle between Toyotomi Hideyoshi and Tokugawa Ieyasu.
Tokugawa Ieyasu took up a position in the ruins of Nobunaga’s former Komaki Castle. Various small skirmishes took place around the Komaki area, and as far away as modern day Mie Prefecture, but on the whole appeared to be a quiet battle, with neither Hideyoshi nor Ieyasu entering into any major conflict.
After some time, it was suggested by Ikeda Tsuneoki that as Ieyasu and the bulk of his forces are stationed on Mt. Komaki, the Tokugawa stronghold, Okazaki Castle must be understaffed, and that if the Toyotomi were to secretly move on Okazaki and take it, Ieyasu would be cut off and destroyed. Ikeda Tsuneoki’s 6,000 troops with support from Mori Nagayoshi’s 3,000, Hori Hidemasa and his 3,000 samurai, Hideyoshi’s heir, Hidetsugu with 8,000 troops departed quietly for Mikawa.
Ieyasu learned of the contingent’s move towards Okazaki through information “provided by farmers of Iga Province”. (What would farmers from Iga be doing in the in the Owari / Mikawa region, and why would they be reporting to Ieyasu? Because they were probably what we would now call Ninja.)
The Ikeda attacked Iwasaki Castle, which slowed their momentum, and allowed the Tokugawa to give chase, who caught up with the Mori, Hori and Toyotomi around Nagakute, leading to a violent two hour battle.
Over the folling weeks, more fighting took place across Owari and Ise, until Oda Nobukatsu, who had brought Ieyasu into this conflict, went behind Ieyasu’s back and quietly made peace with the man he saw as a usurper and was hoping to oust, Hideyoshi! The Toyotomi and Tokugawa forces slowly withdrew to their respective domains. Ieyasu and Hideyoshi were later to make peace again.
Letter
As mentioned, a letter sent by Hashiba (Toyotomi) Hideyoshi to his younger brother Hidenaga during the Battle of Komaki and Nagakute has been newly discovered at the Tanaka Honke Museum in Suzaka City, Nagano Prefecture. The battle situation is described in a light-hearted manner, and experts say that this is a valuable document that reveals the relationship between the brothers.
The letter is said to have been obtained by the head of the Tanaka clan during the Edo period. In July of this year, director of the museum Mr. Tanaka Shinjuro (49), asked Associate Professor Murai Yuki of the Historiographical Institute of the University of Tokyo to investigate the letter, which had been kept in a storehouse. As a result, it was confirmed that it was indeed a newly discovered letter based on Hideyoshi's signature, the contents of the letter, and the high quality of the paper.
The letter was issued on June 18, 1584, and describes Hideyoshi's attack on Kuroda and Ichinomiya in Owari (Aichi Prefecture) and setting them on fire. In the letter to Hidenaga, long considered Hideyoshi’s right hand man, Hideyoshi jokes that "you must have seen the smoke," as he reports the battle situation, giving us a glimpse into the relationship between the two men.
It also says, "Have you reached Kobe Castle, too?" According to Associate Professor Murai, this too is a new discovery, showing that Hidenaga was guarding Kobe in Ise at this time. It also warns, "It is important to be vigilant when it comes to ships," showing that Hideyoshi was also concerned about control of the seas.
It is reported that very few original letters sent by Hideyoshi to Hidenaga remain. Director Tanaka said, "I am impressed that they have been preserved to this extent, even though some documents have been thrown away in the past because it was unclear whether they were genuine or not."
The newly discovered letter is currently being shown in a special exhibition will run until December 15th at the Tanaka Honke Museum in Suzaka City, Nagano Prefecture.
The discovery is timely as the NHK annual historical Taiga Drama series for 2026 is set to focus on the brothers, Hideyoshi and Hidenaga and their humble beginnings as lowly ranked footsoldiers living in what is now Nakamura Ward of Nagoya City, and their subsequent rise to national power.
Original sources include:
https://news.yahoo.co.jp/articles/630f80e7cf7fc480c0367c27c916a466d9814b96