In 1335, the Shiina clan built Uozu Castle as an auxiliary stronghold supporting Matsukura Castle. By 1570, it had fallen under the control of the Uesugi clan, rapidly emerging as a strategic fortress in Etchū Province. For many years, Kawada Nagataka served as its commander.
Following the death of the renowned daimyo Uesugi Kenshin in 1578, his domain plunged into a prolonged civil conflict known as the Otate no Ran. Seizing the opportunity, Oda Nobunaga dispatched his top generals—Shibata Katsuie and Sassa Narimasa—from the Hokuriku region toward Etchū’s borders.
By 1581, Oda’s forces captured Toyama Castle and advanced into Etchū. Katsuie and Narimasa systematically expelled both Uesugi’s retainers and remaining Ikkō-ikki forces. Realizing the severity of the threat, Uesugi Kagekatsu (1556–1623), Kenshin’s heir, hurriedly reinforced Uozu Castle with trusted vassals.
By March 1582, combined Oda armies under Shibata, Sassa, Maeda Toshiie, and Sakuma Morimasa had attacked both Matsukura and Uozu. Approximately 10,000 besiegers confronted around 4,000 defenders at Uozu.
Unlike the mountain-stronghold of Matsukura, Uozu was a flatland castle (hirajō) near Toyama Bay, featuring two defensive lines: the central hommaru and an outer ninomaru. The hommaru was a near-square enclosure surrounded by a water moat with a single bridge at the entrance. The ninomaru corked around three sides in a “U” shape and also had its own moat. The castle lacked stone walls, yagura towers, or a donjon—instead, it relied on earthen ramparts (dorui) topped with clay walls (dobei), and watchtowers at each corner of the hommaru.
When Oda’s army appeared, the castle’s commanders sent an urgent plea to Kagekatsu. However, internal Uesugi strife, betrayal by Shibata Shigeie, and threats in Kaga and Shinano caused a delay. Meanwhile, Oda’s forces wore down the defenders with constant assaults.
In early May, Kagekatsu himself departed from Kasugayama Castle, captured the strategic Tenjin Hill, but failed to break the siege. Upon hearing news of a possible attack on Kasugayama, he withdrew. Left unsupported and starved of supplies, the Uozu garrison rapidly deteriorated.
After nearly three months of siege, in early June, thirteen senior Uesugi commanders chose to commit seppuku rather than surrender, and Uozu Castle fell. Oda’s forces had planned to advance into Echigo, but news of Nobunaga’s death in the Honnō-ji Incident sparked panic. Many commanders ordered a retreat from Etchū, and Uozu returned to Uesugi control without further fighting.
See also
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The siege of the Ishimama Honganji monastery
In Japanese history, the siege of Ishiyama Hongan-ji — the main stronghold of the Ikkō-ikki movement during Oda Nobunaga’s campaign — is considered the longest, lasting from August 1570 to August 1580.
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The Battle of Norada
The Battle of Norada is a striking example of a clash during the Sengoku Jidai period, when numerical superiority did not always guarantee victory, even in open battle.
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Battles of Kawanakajima
The Battles of Kawanakajima were a series of fierce conflicts during Japan's Sengoku period, waged between Takeda Shingen of Kai Province and Uesugi Kenshin of Echigo Province from 1553 to 1564. These battles centered around the strategic Kawanakajima plain, lying between the Sai and Chikuma rivers in northern Shinano Province, now within Nagano City. The rivalry began when Shingen took control of Shinano, forcing Ogasawara Nagatoki and Murakami Yoshikiyo to seek refuge with Kenshin, prompting repeated clashes.
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Siege of Odawara 1590
The Third Siege of Odawara in 1590 was a pivotal moment in Toyotomi Hideyoshi's efforts to neutralize the Hojo clan as a challenge to his authority. In the months leading up to the siege, the Hojo made significant, hurried improvements to the castle's defenses as Hideyoshi’s intentions became clear. However, despite Hideyoshi's overwhelming force, there was little actual combat during the siege.
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Battle of Tenmokuzan
The Battle of Tenmokuzan in 1582 is remembered as the final stand of the Takeda clan in Japan. This battle marked the last attempt by Takeda Katsuyori to resist Oda Nobunaga's relentless campaign against him. Fleeing from his pursuers, Katsuyori set fire to his fortress at Shinpu Castle and sought refuge in the mountains at Iwadono, a stronghold held by his loyal retainer, Oyamada Nobushige. However, Oyamada betrayed Katsuyori, denying him entry. Left with no other option, Katsuyori committed suicide alongside his wife, while the remnants of his army made a valiant effort to hold off their attackers.
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Battle of Oshu
The Northern Fujiwara clan had governed the Mutsu and Dewa provinces since 1087, maintaining their rule for over a century by 1189. The clan was founded by Fujiwara no Kiyohira, alongside Minamoto no Yoshiie, who established their independence in Hiraizumi, located in present-day Iwate Prefecture. Under Kiyohira, and later his successors Fujiwara no Motohira and Fujiwara no Hidehira, the Northern Fujiwara reached the height of their power in the Tohoku region. They infused the area with Kyoto culture and constructed significant temples, such as Chuson-ji, founded in 1095.
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Battle of Omosu
The 1580 Battle of Omosu (Omosu no Tatakai) was one of many conflicts between the Hojo and Takeda clans during Japan's Sengoku period. What sets this battle apart is its rarity as one of the few naval engagements in pre-modern Japan. The conflict occurred off the coast of the Izu Peninsula, involving the fleets of Hojo Ujimasa, the leader of the Hojo clan, and Takeda Katsuyori, the head of the Takeda clan.
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The Battle of Azukizaka
The Battle of Azukizaka, also known as the Battle of Bato-ga-hara, occurred in 1564, as Tokugawa Ieyasu aimed to quash the emerging threat of the Ikko-ikki, a coalition of monks, samurai, and peasants strongly opposed to samurai rule.
