... is Samurai/Daimyo during Sengoku Period. He ruled Yamato with one million Koku, and promoted to Dainagon (大納言). He was also called as Yamato-Dainagon.
Under Nobunaga's Samurai
He was born as the younger brother of Toyotomi Hideyoshi, and supported him for entire success from the beginning of his story. There is no record said when he started to serve Hideyoshi, but considering with Hideyoshi's status as the son of farmer, Hidenaga started serving Hideyoshi right after the wedding of Hideyoshi and his wife Nene around 1564 because Hideyoshi would never had enough money to hire his Samurai before. So, Hidenaga should be the first Hideyoshi's Samurai. Like his brother Hideyoshi, he was also extremely talented to be great samurai to support Hideyoshi just in few years without any kinds of training and education. At this time, he was named Kinoshita Koichiro after Hideyoshi's name (Kinoshita Tokichiro).
Hidenaga managed all Hideyoshi's samurai and official works as the vice commander of Hideyoshi almost all the time because Hideyoshi was always at Nobunaga's place. When Nobunaga attacking Mino, he fought under Hidenyoshi. When Hideyoshi was called by Nobunaga, Hidenaga stayed and protected the spot with Hideyoshi's army.
After victory against Asakura clan, Hideyoshi was given Nagahama Castle, and he become the vice castle lord. At this time, he hired right arm, Todo Takatora. He named himself Nagahide after Hideyoshi named himself from Tokichiro to Hideyoshi. Nagahide is the combination name of Nobunaga and Hideyoshi. In 1574, he went and finished a punitive expedition of Nagashima Ikko Ikki instead of Hideyoshi.
After Hidehoshi became the commander in chief for Chugoku reagion, Hidenaga conquered Tajima area. In the letter of Hideyoshi to Kuroda Jyosui, Hideyoshi said Hidenaga is the most important person in Hideyoshi's samurai. He defeated Takeda Castle and become the vice lord of the castle. During the confusion by betray of many samurai against Nobunaga in 1578, he fought many battles to support Hideyoshi to conquer Harima and Tango. In 1580, Bessio clan had been defeated by Hideyoshi, Hidenaga become the castle lord of Deishi Castle and also he was given Tajima area to become Daimyo of 105,000 koku. Also, he governed the silver mining of Ikuno.
As the first Samurai of Hideyoshi
In 1582, Nobunaga died at Honnoji Temple, He joined the battle of Yamazaki under his brother. He also stayed at Tennozan to protect against the invading from Mori Motonari with very few army because Hideyoshi took major amount of army to against Mitsuhide.
In 1583, He joined the battle of Shizugatake (Hideyoshi vs Shibata Katsuie). Hideyoshi moved and emptied his army at Nagahama so that Sakuma Narimasa moved his position and attacked Nagahama Castle. Hidenaga's task was protect the Nagahama Castle with very few army against Sakuma. Hidenaga lost Nakagawa Kiyohide, but succeeded to protected until Hideyoshi back from Mino. After this great victory, he was given Tajima and Harima area and moved Himeji Castle. In 1584, at the battle of Owari Nagakute, Hidenaga moved his army to Moriyama to watch Oda Nombukatsu, and negotiated him to stop the battle.
When his brother become the successor of Nobunaga, Hidenaga change his name from Nagahide to Hidenaga to show that Hideyoshi was now the only his master.
In 1585, he joined the conquer of Kisyu with Hideyoshi as the vice commander. After the victory, he was given Kii and Izumi and became Daimyo of 640,000 koku. He ordered Kiyotora to built Wakayama Castle. In the same year, He became the commander in chef and conquered Shikoku. He defeated Chosokabe clan and ruled Shikoku.
For this victory of Shikoku, he was given Yamato, and became Daimyo of 1.16 million koku. His lands, Yamato, Kii, and Izumi, were not easy to rule because temples had still strong power and influence to the people. However, he never made any kinds of problem with them and ruled peacefully.
Around 1586, he was getting sick often. Many high priest of temples including Honganji Kennyo, send many gifts and letter to wish his recovery.
In 1586, Tokugawa Ieyasu visited Hidenaga. This meeting was held with only Hideyoshi, Hidenaga, Ieyasu and Nasano Nagamasa. After this meeting, Ieyasu showed his resignation to Hideyoshi.
In 1587, the battle of Kyusyu, he was the chef commander of the army and lead his company to defeat Hyuga. At the battle of Mimikawa, he defeated Shimazu Iehisa and conquered all Kyusyu. For this victory, he was entitled Dainagon.
In 1590, Hidenaga died at Koriyama Castle (51 years old).
Hideyoshi stated
"Ask Sen no Rikyu for any private matter, and ask Hidenaga for all public matter."
Hidenaga supported Hideyoshi for all his success, never lost any battles, managed all the man relationship problem of Hideyoshi, governed many hard cities without any problems, and built one of the strong government for Hideyoshi. All of his life was helping his brother. He was the part of Hideyoshi and when Hideyoshi lost Hidenaga, he lost half of himself and nothing happened good for Hideyoshi.
If he lived longer than Hideyoshi, the history might be different.
Hidenaga's samurai, Nakai Masakiyo, Todo Takatora and Kobori Enshu were hired by Ieyasu and built many great castle including Edo Caslte and beautiful gardens. They influenced the architectures of Edo style building.