Siege of Ichijōdani Castle
Date: Eighth month of Tenshō 1 (1573)
Location: Tonezaka and the town and castle of Ichijōdani in Echizen Province
Synopsis: As a participant in a campaign to oppose Nobunaga known as the Nobunaga Encirclement, Asakura Yoshikage led an army into Ōmi Province in an effort to assist his ally, Azai Nagamasa. In the wake of losses in Ōmi, the Asakura retreated under pressure to their home of Ichijōdani in Echizen Province. A subsequent invasion by the Oda army forced Yoshikage to flee to the northern part of the province, whereupon he was betrayed by a nephew named Asakura Kageakira and took his own life while Ichijōdani was burned down and the Asakura as a clan were extinguished.
The Siege of Ichijōdani Castle occurred in the eighth month of Tenshō 1 (1573) at the main base of the Asakura clan at Ichijōdani in Echizen Province. The conflict was waged between Oda Nobunaga and Asakura Yoshikage, the eleventh head of the Asakura and sengoku daimyō of Echizen. Referring to the conflict as a siege of Ichijōdani Castle is a restrictive interpretation so this is also referred to as the Battle of Tonezaka after the name of the location where the battle occurred.
Surrounding of Odani Castle
In opposition to Od Nobunaga, Ashikaga Yoshiaki, the fifteenth shōgun of the Muromachi bakufu, formed the Nobunaga Encirclement in an effort to resist. Azai Nagamasa and Asakura Yoshikage fought as members of the resistance against Nobunaga, but confronted precarious circumstances. In the fourth month of 1573, Takeda Shingen, the sengoku daimyō of Kai Province who was also a member of the resistance, died. In the seventh month, the leader of the resistance, Yoshiaki, was expelled from Kyōto in an event known as the Siege of Makishima Castle. Those supporting the resistance were at a clear disadvantage.
On 8/8, Nobunaga led an army of 30,000 soldiers, departing from Gifu Castle to invade Ōmi Province. Azai Nagamasa responded by holing-up in Odani Castle with a contingent of 5,000 soldiers. Asakura Yoshikage overcame opposition in the family, leading 20,000 troops as reinforcements for Nagamasa, establishing their main base in Yogo. Atsuji Sadayuki, a bushō under Nagamasa and the lord of Yamamotoyama Castle, betrayed the Azai in favor of Nobunaga so the Oda army felled Tsukigase Castle and were able to lay siege to the west of Odani Castle. Meanwhile, with respect to the Asakura, a senior retainer named Uozumi Kagekata refused to deploy troops on the grounds of fatigue after several years of operations. As a result, Yoshikage himself had to deploy. From around this time, the Asakura clan began to show signs of collapse owing to internal conflicts coupled with maneuvers by the Oda.
With the aim of providing rear-guard support to Odani Castle, Yoshikage established a position on Mount Tanakami to the northwest behind the castle. At the same time, he built a series of fortresses including Ōzuku fortress to serve as a defense for Odani Castle. On 8/10, the main division of the Oda army set-up an encampment on Mount Yamada located between Mount Tanakami and Odani Castle, serving as a means to both visibly provoke and restrict the movement of the Asakura. The forces under Nobunaga also constructed fortresses and bases at critical locations in the area, making plans to encircle Odani Castle and the Asakura army.
On 8/12, Ōmi was swept by torrential wind and rain. Nobunaga determined that the weather would distract the enemy forces, so he considered how to take advantage of the opportunity. Nobunaga then led a contingent of 1,000 solders and cavalry from his main base on a surprise attack against Ōzuku Castle defended by the Asakura forces. This fortress was downhill to the south of Mount Yamada, perched higher than Odani Castle in the same mountain chain, serving as the forward-operating base of the Asakura to oppose the Oda army.
Even if the Asakura anticipated an attack by the enemy forces in the midst of the wind and rain, they could not see them so surrendered. The Oda could have killed the captured soldiers, but instead Nobunaga intentionally released them, sending them toward Yoshikage’s base. After learning of the fall of Ōzuka, Nobunaga expected that Yoshikage would definitely retreat, and planned to chase them. Next, Nobunaga assaulted and captured Yōnoyama Castle defended by warrior monks from the Heisen Temple in Echizen who were aligned with the Asakura. He then set these forces free as well.
After placing troops in these two fortresses, Nobunaga was convinced that the Asakura would retreat and positioned senior retainers including Sakuma Nobumori, Shibata Katsuie, Takigawa Kazumasu, Kinoshita Hideyoshi, and Niwa Nagahide on the front lines, giving orders not to lose a good opportunity.
Battle of Tonezaka
On 8/13, after learning of the fall of Ōzuka fortress, Yoshikage assessed the situation. The Oda army had 30,000 troops compared to the Asakura army of 20,000. Moreover, senior retainers were absent from the main force of the Asakura, and morale low, so, without a prospect for victory, he decided to withdraw.
As the Asakura began their withdrawal, Nobunaga himself commanded his main division to launch a pursuit of the Asakura forces. Vanguard forces who had earlier received orders from Nobunaga were delayed and, as a result, remonstrated by Nobunaga. Sakuma Nobumori voiced his opposition, causing Nobunaga to become angry.
From the onset, members of the Asakura family were divided in their opinions with respect to the deployment to Ōmi. Internal maneuvers by the Oda served to undermine the zeal of the Asakura army and, during the chaos caused by attacks during the withdrawal, the forces were slaughtered. Aiming to reach Hikida Castle, Yoshikage headed toward Tonezaka but was pursued by Oda forces led by Nobunaga himself. During the retreat from Yogo to Tonezaka and Tsuruga, the Asakura army was under pressure from the Oda. According to historical records of the Oda, over 3,000 soldiers were killed in action. The references to 38 bushō and 3,000 rank-and-file soldiers may, however, be inflated. Some of the Asakura soldiers stood their ground while others turned back to confront the Oda, fighting valiantly. Nevertheless, many of the bushō comprising the nucleus of the main division of the Asakura army, including family members such as Asakura Kageyuki (the lord of Kita-no-shō Castle), Asakura Michikage (who was seventeen years old at the time), in addition to retainers such as Yamazaki Yoshiie and Kawai Yoshimune, and Saitō Tatsuoki (serving as a guest commander of the Asakura), were all killed in action.
On 8/14, the Oda army engaged in an all-out attack during their pursuit of the Asakura army. As a result, the expeditionary forces of the Asakura sent to Ōmi operating under the command of the main division were almost completely decimated. Yoshikage returned to Ichijōdani only with his own units.
Siege of Ichijōdani Castle
On 8/15 and 8/16, Nobunaga recognized the contributions of allied bushō and allowed them to rest. On 8/17, he organized his large army and had a former retainer of Yoshikage named Maeba Yoshitsugu serve as their guide to invade Echizen.
Meanwhile, on 8/15, Yoshikage returned to his base at Ichijōdani Castle but bushō from the province were aware of their inferior number of allies so did not hasten to join while Yoshikage assembled a total of 500 troops (excluding attendants).
At this point, Asakura Kageakira, who served as the gunji, or governor, of the Ōno District in northern Echizen, located at Iyama Castle, recommended to Yoshikage to abandon Ichijōdani and to proceed to Ōno to reconstitute his forces. As a basin area, the Ōno District allowed for a robust defense. To plan a revival, Kageakira proposed that Yoshikage turn to the Heisen Temple with whom the Asakura had an alliance. The warrior monks of the Heisen Temple who were known for being an intrepid band had deployed to Ōmi to defend Chōnoyama Castle. By this time, however, the monks had already colluded with Nobunaga and obtained recognition of their rights to the landholdings of the Heisen Temple. This is said to have occurred through the maneuvers of Kinoshita HIdeyoshi.
On 8/18, Nobunaga attacked the town of Ichijōdani, siezing control and burning it down. Among the defenders, those making the most notable contributions were former retainers of the Wakasa-Takeda clan under their lord Takeda Motoaki, who were prisoners of the Asakura. At this time, several hundred of them fought against the Oda army as a demonstration of loyalty to the Asakura.
Prior to this event, Yoshikage fled Ichijōdani with only his own troops and, upon the urging of Kageakira, went to the Ōno District. On 8/20, at the Rokubō-kenshō monastery proposed by Kageakira as a temporary place to stay, Yoshikage was thoroughly surrounded by 200 troops under Kageakira who betrayed their lord. As the attendants fought and died, Yoshikage took his own life. Kageakira then brought Yoshikage’s head, along with Yoshikage’s mother (Kōtokuin), wife and children as hostages, and surrendered to Nobunaga.
As a condition of the surrender, the lives were spared of very close relatives of Yoshikage including his infant son and designated heir (Aiōmaru) and cherished consort (Koshōshō). Some of Yoshikage’s attendants did not martyr themselves and survived the battle. Efforts were made to negotiate for their lives and future status but the dependents of Yoshikage were executed by the Oda army while in transit.
A portion of the bushō and family members joined the Oda, but were not heavily relied upon. Other relatives and bushō later plotted a revolt and, together with the Ikkō-ikki, rose to action but, several years later, owing to the annihilation of the Echizen Ikkō-ikki, became powerless in front of Nobunaga’s subsequent invasion of Echizen.
Later, the Oda forces returned to northern Ōmi and attacked Odani Castle, devastating the Azai clan. Owing to the elimination of the Asakura clan in this battle, Nobunaga’s territory expanded to encompass Echizen and Wakasa provinces.