was a naval commander during Japan's Sengoku Period, under Oda Nobunaga

Oda Nobunaga

was the initiator of the unification of Japan under the shogunate in the late 16th century, which ruled Japan until the Meiji Restoration in 1868. He was also a major daimyo during the Sengoku period of Japanese history. His opus was continued, completed and finalized by his successors Toyotomi...

, and later, Toyotomi Hideyoshi

Toyotomi Hideyoshi

was a daimyo warrior, general and politician of the Sengoku period. He unified the political factions of Japan. He succeeded his former liege lord, Oda Nobunaga, and brought an end to the Sengoku period. The period of his rule is often called the Momoyama period, named after Hideyoshi's castle...

.

In the 1570s, Kuki allied himself with Oda Nobunaga

Oda Nobunaga

was the initiator of the unification of Japan under the shogunate in the late 16th century, which ruled Japan until the Meiji Restoration in 1868. He was also a major daimyo during the Sengoku period of Japanese history. His opus was continued, completed and finalized by his successors Toyotomi...

, and commanded his fleet, supporting land-based attacks on the Ikkō-ikki

Ikko-ikki

', literally "Ikkoshū Uprising", were mobs of peasant farmers, Buddhist monks, Shinto priests and local nobles, who rose up against samurai rule in 15th to 16th century Japan. They followed the beliefs of the Jōdo Shinshū sect of Buddhism which taught that all believers are equally saved by Amida...

. In 1574, his aided ensured a victory for Nobunaga

Oda Nobunaga

was the initiator of the unification of Japan under the shogunate in the late 16th century, which ruled Japan until the Meiji Restoration in 1868. He was also a major daimyo during the Sengoku period of Japanese history. His opus was continued, completed and finalized by his successors Toyotomi...

 in his third attempt to attack the Nagashima

Nagashima

' was a series of fortresses and fortifications controlled by the Ikkō-ikki, a sect of warrior monks in Japan's Sengoku period who opposed samurai rule. It was attacked and destroyed by Oda Nobunaga in the 1570s...

 fortress. In 1576, he was defeated at Kizugawaguchi

Battles of Kizugawaguchi

The two were fought during Oda Nobunaga's attempted sieges of the Ishiyama Hongan-ji in Osaka. The Hongan-ji was the primary fortress of the Ikkō-ikki, mobs of warrior monks, priests, and farmers who opposed Oda's rule. He ordered one of his admirals, Kuki Yoshitaka, to organize a blockade against...

 by the Mōri clan

Mori clan

The Mōri clan was a family of daimyō, descended from Ōe no Hiromoto and established themselves in Aki Province. Their name was derived from a shōen in Mōri, Aikō District, Sagami Province. The generation of Hiromoto began to name themselves Mōri.After the Jōkyū War, Mōri was appointed to the jitō...

 fleet, but 1578 brought victory in the second Battle of Kizugawaguchi

Battles of Kizugawaguchi

The two were fought during Oda Nobunaga's attempted sieges of the Ishiyama Hongan-ji in Osaka. The Hongan-ji was the primary fortress of the Ikkō-ikki, mobs of warrior monks, priests, and farmers who opposed Oda's rule. He ordered one of his admirals, Kuki Yoshitaka, to organize a blockade against...

, in which Kuki used 'iron ships' to repel the arrows and musket balls of the opposing Mōri clan's ships.

In 1587, he led Toyotomi Hideyoshi's

Toyotomi Hideyoshi

was a daimyo warrior, general and politician of the Sengoku period. He unified the political factions of Japan. He succeeded his former liege lord, Oda Nobunaga, and brought an end to the Sengoku period. The period of his rule is often called the Momoyama period, named after Hideyoshi's castle...

 fleet in a campaign in Kyūshū

Kyushu

is the third largest island of Japan and most southwesterly of its four main islands. Its alternate ancient names include , , and . The historical regional name is referred to Kyushu and its surrounding islands....

, alongside Konishi Yukinaga

Konishi Yukinaga

Konishi Yukinaga was a Kirishitan daimyō under Toyotomi Hideyoshi. He was the son of a wealthy Sakai merchant, Konishi Ryūsa...

, Wakizaka Yasuharu and Katō Yoshiaki

Kato Yoshiaki

was a Japanese daimyo of the late Sengoku Period to early Edo Period who served as lord of the Aizu Domain. A retainer of Toyotomi Hideyoshi, he fought in the battle of Shizugatake in 1583, and soon became known as one of the shichi-hon-yari , or Seven Spears of Shizugatake, Hideyoshi's seven most...

. Three years later, along with Wakizaka Yasuharu and Kato Yoshiaki he went on to lead the Siege of Odawara

Siege of Odawara (1590)

The third ' occurred in 1590, and was the primary action in Toyotomi Hideyoshi's campaign to eliminate the Hōjō clan as a threat to his power. The months leading up to it saw hasty but major improvements in the defense of the castle, as Hideyoshi's intentions became clear...

 and the Siege of Shimoda

Siege of Shimoda

The siege of Shimoda was a naval siege conducted against a coastal Hōjō fortress in Izu Province. This was concurrent with the larger siege of Odawara, and though the commanders of the besieging force were among Hideyoshi's greatest generals, they were held off by a mere 600 defenders for four...

. He continued in his role as commander of Hideyoshi's fleet, launching an invasion of Korea

Korea

Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

 in 1592 from his flagship Nipponmaru.

In the Battle of Sekigahara

Battle of Sekigahara

The , popularly known as the , was a decisive battle on October 21, 1600 which cleared the path to the Shogunate for Tokugawa Ieyasu...

, Kuki Yoshitaka fought alongside the Toyotomi forces, while his son Kuki Moritaka

Kuki Moritaka

was a general and admiral in the service of Tokugawa Ieyasu, and the son of Kuki Yoshitaka, one of Toyotomi Hideyoshi's top generals.In the last years of the 16th century, Kuki Moritaka supported Tokugawa Ieyasu in his bid for power, while his father fought for the opposing side, supporting Ishida...

 joined the opposing force, under Tokugawa Ieyasu

Tokugawa Ieyasu

 was the founder and first shogun of the Tokugawa shogunate of Japan , which ruled from the Battle of Sekigahara  in 1600 until the Meiji Restoration in 1868. Ieyasu seized power in 1600, received appointment as shogun in 1603, abdicated from office in 1605, but...

. As a result, he committed seppuku

Seppuku

is a form of Japanese ritual suicide by disembowelment. Seppuku was originally reserved only for samurai. Part of the samurai bushido honor code, seppuku was either used voluntarily by samurai to die with honor rather than fall into the hands of their enemies , or as a form of capital punishment...

.