He was born at Akanabe in Atsumi District, Mino Province, the eldest son of Hori Hideshige, a retainer of Saitō Dōsan. His common name was Kyūtarō. As a child he is said to have been raised by an uncle who had become a priest of the Ikkō sect, together with his cousin Hori Naomasa. Naomasa later became the senior retainer who supported Hidemasa most closely, his partner for life.
He served first Ōtsu Nagamasa and then Kinoshita Hideyoshi, but while still a boy his talent was recognized and he was taken on as a page by Oda Nobunaga. Nobunaga had many capable aides such as Sugaya Nagayori and Hasegawa Hidekazu, and Hidemasa worked alongside them attending to their lord and carrying his orders.
While still in his teens, he was entrusted as magistrate overseeing work on the Honkoku-ji in Kyoto, the temporary residence of shogun Ashikaga Yoshiaki. From then on Hidemasa handled many magistrate duties and secured his place as Nobunaga's aide. His ability to manage tasks precisely would later serve him well as a commander too.
Following his part in suppressing the Echizen Ikkō uprising two years earlier, in this year's attack on Saika in Kii he left Nobunaga's headquarters to lead a unit with Sakuma Nobumori and Hashiba Hideyoshi. The next year at the siege of Arioka Castle he commanded gunners, showing his ability not only as an aide but also as a field commander.
At the Azuchi religious debate, in which monks of the Jōdo and Hokke sects argued over the merits of their teachings at Azuchi, site of Nobunaga's castle, he served as magistrate with Sugaya Nagayori, Hasegawa Hidekazu and others. The next year he also helped build a residence for the missionaries. Through his uncle, an Ikkō priest, he is thought to have dealt with the Honganji as well.
In the Iga campaign he led the unit advancing by the Shigaraki route and fought through to the end. Recognized for this along with his service against Araki Murashige and in subduing the Echizen Ikkō uprising, he was given Nagahama Castle in Ōmi and twenty-five thousand koku by Nobunaga. Hidemasa took a great step from aide to castle-holding lord.
He was with Hideyoshi in Bitchū as Nobunaga's envoy when news of the Honnō-ji Incident arrived. Hurrying back with Hideyoshi, he fought in the vanguard at the Battle of Yamazaki with Nakagawa Kiyohide, Takayama Ukon and others. He then cornered Akechi Hidemitsu at Sakamoto Castle in Ōmi, contributing greatly to the defeat of the Akechi forces who had overthrown Nobunaga.
As a result of the Kiyosu Conference he was given part of Ōmi and appointed guardian of Sanbōshi, Nobunaga's grandson and designated heir of the Oda house. In the struggles within the Oda house that followed he sided with Hideyoshi, and he is thought to have been the first person outside Hideyoshi's family to receive the Hashiba surname, showing Hideyoshi's deep trust.
In the settlement after the Battle of Shizugatake he was given Sawayama Castle in Ōmi and also received a court title. While Hidemasa campaigned in many places, his father Hideshige and his younger brother governed his lands as keepers of Sawayama Castle. In this way a family-wide system supporting Hideyoshi's rise to rule was built.
In the Battle of Komaki and Nagakute he joined, as the third unit, the operation to strike at Tokugawa Ieyasu's home base of Mikawa. When the unit of Hashiba Hidetsugu ahead of him collapsed under a Tokugawa surprise attack, he gathered the fleeing soldiers, set up camp at Hinokigane and defeated pursuers such as Sakakibara Yasumasa. Learning that Ieyasu himself had come out, he withdrew without taking risks.
He was granted more than one hundred eighty thousand koku at Kitanosho in Echizen and became a great daimyō known as the "Chamberlain of Kitanosho." Tales such as his carrying a load himself to judge a dispute over its weight show a character that thought carefully of those beneath him, and he was praised as the "master Kyūtarō."
In Toyotomi Hideyoshi's pacification of Kyushu, he was entrusted with the vanguard as Hideyoshi headed west. During this campaign an attendant went mad and attacked him from behind, but Hidemasa is said to have turned instantly and repelled him. Hideyoshi trusted him so deeply as to give him the lead in important campaigns.
In the Odawara campaign he was made commander of the left wing, took Yamanaka Castle in Hakone, pushed on to the Hayakawa entrance of Odawara and set his headquarters at Kaizō-ji. But he fell ill in camp and died suddenly. Hideyoshi is said to have asked about his condition again and again. A self-portrait he painted before setting out is kept at his family temple.
Saitō DōsanOda NobunagaToyotomi HideyoshiAshikaga YoshiakiTokugawa IeyasuSakakibara YasumasaTakayama Ukon
Nene (Kōdai-in)Sakakibara YasumasaTakayama UkonMōri TerumotoSuminokura RyōiGamō UjisatoTōdō TakatoraUesugi Kagekatsu
People of the Sengoku/Azuchi-Momoyama period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.