Oda Nobunaga was born on 23 June 1534 in Nagoya, Owari Province, the second son of Oda Nobuhide, the head of the powerful Oda clan and a deputy shugo (military governor) with land holdings in southern Owari, and his wife Dota Gozen. Nobunaga is said to have been born in Nagoya Castle, the future seat of the Owari Domain, although this is subject to debate. Nobunaga was given the childhood name of Kippōshi (吉法師), and through his childhood and early teenage years became well known for his bizarre behavior, receiving the name of Owari no Ōutsuke (尾張の大うつけ, The Great Fool of Owari). Nobunaga was known to run around with other youths from the area, without any regard to his own rank in society, and with the introduction of firearms into Japan he became known for his fondness for tanegashima guns.

In 1551, Oda Nobuhide died unexpectedly; Oda Nobuhiro, Nobuhide’s eldest son, become the new head of the Oda clan, and Nobunaga was said to have acted outrageously during his funeral, throwing ceremonial incense at the altar. Although Nobunaga was Nobuhide’s legitimate heir, a succession crisis occurred when some of the Oda clan were divided against him. Hirate Masahide, a valuable mentor and retainer to Nobunaga, performed seppuku to startle Nobunaga into his obligations. Nobunaga, collecting about a thousand men, suppressed members of his family who were hostile to his rule and their allies.

Later in 1551, an Imagawa army under the command of Imagawa Sessai laid siege to the Anjo castle where Oda Nobuhiro was living. Nobuhiro was trapped by the Imagawa clan, but was saved when Nobunaga handed over one of his hostages, Matsudaira Takechiyo – later known as Tokugawa Ieyasu – to make up for not lifting the siege of Anjō. Afterwards, Nobuhiro was forced to step down and allow Nobunaga to be the new head of Oda clan. Later on, Nobuhiro plotted against Nobunaga with the assistance of Saitō Yoshitatsu, but Nobunaga forgave Nobuhiro after the plot failed.

In 1553, Nobuhide’s younger brother, Oda Nobutomo, took over Kiyosu Castle with the support of Shiba Yoshimune. After Yoshimune revealed to Nobunaga an assassination plot in 1554, Nobutomo had Yoshimune put to death. The next year, Nobunaga re-took Kiyosu Castle and captured his uncle, forcing him to commit suicide.

Nobunaga’s main rival as head of the Oda clan was his younger brother, Oda Nobuyuki. In 1555, Nobunaga defeated Nobuyuki at the Battle of Ino, though Nobuyuki survived and began plotting a second rebellion. In 1556, Nobunaga destroyed a rival branch of the Oda clan located in Kiyosu Castle. At the same time, Nobunaga sent an army to Mino Province to aid his father-in-law Saitō Dōsan, after Dōsan’s son, Saitō Yoshitatsu, turned against him. The campaign failed, as Dōsan was killed in the Battle of Nagara-gawa, and Yoshitatsu became the new master of Mino. In 1557, Nobuyuki was defeated by Nobunaga’s retainer Ikeda Nobuteru. Nobunaga killed Nobuyuki at Kiyosu Castle and destroyed Suemori Castle.

In 1558, Nobunaga protected Suzuki Shigeteru in the Siege of Terabe. Shigeteru had defected to Nobunaga’s side from Imagawa Yoshimoto, a daimyō from Suruga Province and one of the most powerful men in the Tōkaidō region. By 1559, Nobunaga had eliminated all opposition within the Oda clan and established his uncontested rule in Owari Province.

Imagawa Yoshimoto was a long-time opponent of Nobunaga’s father, and had sought to expand his domain into Oda territory in Owari. In 1560, Imagawa Yoshimoto gathered an army of 25,000 men they took Washizu fortress and started his march toward the capital city of Kyoto, with the pretext of aiding the frail Ashikaga Shogunate. The Matsudaira clan of Mikawa Province also joined Yoshimoto’s forces, they took Marune fortress. Against this, the Oda clan could rally an army of only 2,000 to 3,000 men. Advisers suggested “to stand a siege at Kiyosu” but Nobunaga refused, stating that “only a strong offensive policy could make up for the superior numbers of the enemy”, and calmly ordered a counterattack against Yoshimoto.

In June 1560, Nobunaga’s scouts reported that Yoshimoto was resting at the narrow gorge of Dengaku-hazama, ideal for a surprise attack, and that the Imagawa army was celebrating their victories of Washizu and Marune fortress. While Yoshimoto viewed victory ahead, Nobunaga moved towards Imagawa’s camp and set up a position some distance away. An array of flags and dummy troops made of straw and spare helmets gave the impression of a large host, while the real Oda army hurried round in a rapid march to get behind Yoshimoto’s camp. The heat gave way to a terrific thunderstorm, and as the Imagawa samurai sheltered from the rain, Nobunaga deployed his troops. When the storm ceased, they charged down upon the enemy in the gorge, so suddenly that Yoshimoto thought a brawl had broken out among his men, only realizing it was an attack when two of Nobunaga’s samurais, Mōri Shinsuke and Hattori Koheita, charged up at him. One aimed a spear at him, which Yoshimoto deflected with his sword, but the second swung his blade and decapitated him. With his victory in this battle, Oda Nobunaga gained greatly in prestige, and many samurai and minor warlords pledged fealty to him.

Rapidly weakening in the wake of this battle, the Imagawa clan no longer exerted control over the Matsudaira clan. In 1561, an alliance was forged between Oda Nobunaga and Matsudaira Motoyasu (who would become Tokugawa Ieyasu), despite the decades-old hostility between the two clans. Nobunaga also formed an alliance with Takeda Shingen through the marriage of his daughter to Shingen’s son. A similar relationship was forged when Nobunaga’s sister Oichi married Azai Nagamasa of Ōmi Province.

In 1561, Saitō Yoshitatsu, the anti-Nobunaga ruler of Mino, died suddenly of illness and was succeeded by his son, Saitō Tatsuoki. However, Tatsuoki was young and much less effective as a ruler and military strategist compared to his father and grandfather. Taking advantage of this situation, Nobunaga moved his base to Komaki Castle and started his campaign in Mino at the Battle of Moribe and later at Battle of Jushijo in June 1561.

By convincing Saitō retainers to abandon their incompetent and foolish master, Nobunaga significantly weakened the Saitō clan. In 1564, Oda Nobunaga dispatching his retainer, Kinoshita Tōkichirō, to bribery many of the warlords in the Mino area, to defect to Oda clan.

In 1566, Nobunaga charged Kinoshita to built Sunomata Castle on the bank of the Sai River opposite Saitō territory, to serve as a staging point for the Oda forces and was intended to intimidate, surprise and demoralize the enemy. In 1567, the “Mino Triumvirate” (西美濃三人衆, Nishi Mino Sanninshū), Inaba Ittetsu along with Andō Michitari and Ujiie Bokuzen, they agreed together to join the forces of Oda Nobunaga. Eventually mounting a victorious final attack at the Siege of Inabayama Castle. After taking possession of the castle, Nobunaga changed the name of both Inabayama Castle and the surrounding town to Gifu. Nobunaga derived the term Gifu from the legendary Mount Qi (岐山 Qi in Standard Chinese) in China, on which the Zhou dynasty is fabled to have started. Nobunaga revealed his ambition to conquer the whole of Japan, and also started using a new personal seal that read Tenka Fubu (天下布武), which means “All the world by force of arms” or “Rule the Empire by Force”. Remains of Nobunaga’s residence in Gifu can be found today in Gifu Park.

Following Nobunaga’s conquest of Mino in 1567, in an effort to cement an alliance between Nobunaga and rival warlord Azai Nagamasa from Omi Province, Nobunaga arranged for Oichi, his sister, to marry Nagamasa. Nobunaga desired peaceful relations with the Azai clan because of their strategic position in between Oda clan’s land and the capital, Kyoto.

In 1568, Ashikaga Yoshiaki and Akechi Mitsuhide, as Yoshiaki’s bodyguard, went to Gifu to ask Nobunaga to start a campaign toward Kyoto. Yoshiaki was the brother of the murdered 13th shōgun of the Ashikaga Shogunate, Yoshiteru, and wanted revenge against the killers who had already set up a puppet shōgun, Ashikaga Yoshihide. Nobunaga agreed to install Yoshiaki as the new shōgun and, grasping the opportunity to enter Kyoto, started his campaign. An obstacle in southern Ōmi Province was the Rokkaku clan, led by Rokkaku Yoshikata, who refused to recognize Yoshiaki as shōgun and was ready to go to war to defend Yoshihide. In response, Nobunaga launched a rapid attack of Chōkō-ji Castle, driving the Rokkaku clan out of their castles. Other forces led by Niwa Nagahide defeated the Rokkaku on the battlefield and entered Kannonji Castle, before resuming Nobunaga’s march to Kyoto. Later in 1570, the Rokkaku tried to re-take the castle, but they were driven back by Oda forces led by Shibata Katsuie. The approaching Oda army influenced the Matsunaga clan to who submit to the future Shogun. The daimyo Matsunaga Hisahide kept his title by making this decision to ally his clan with the shogun.

On 9 November 1568, Nobunaga entered Kyoto, drove out the Miyoshi clan, who fled to Settsu, and installed Yoshiaki as the “15th shōgun” of the Ashikaga Shogunate. However, Nobunaga refused the title of Shōgun’s deputy (Kanrei) or any appointment from Yoshiaki. As their relationship grew difficult, Yoshiaki secretly started an anti-Nobunaga alliance, conspiring with other daimyos and Ikkō-ikki to get rid of Nobunaga, though Nobunaga showed the Emperor Ōgimachi great respect.

In 1568, the Asakura clan was particularly disdainful of the Oda clan’s increasing power. Furthermore, Asakura Yoshikage was the protector of Ashikaga Yoshiaki, but was not willing to march toward Kyoto. In 1570, Nobunaga launched campaign into the Asakura clan’s domain and besieged Kanagasaki Castle. Azai Nagamasa, to whom Nobunaga’s sister Oichi was married, broke the alliance with Oda to honor the Azai-Asakura alliance, which had lasted for generations. With the help of allied Ikkō-ikki and Rokkaku clan, the anti-Nobunaga alliance sprang into full force, taking a heavy toll on the Oda clan. Nobunaga found himself facing both the Asakura and Azai forces and when defeat looked certain, Nobunaga decided to retreat from Kanagasaki. Later, they clashed at the Battle of Anegawa, at the Ane river near Lake Biwa.

In July 1570, the Oda-Tokugawa allies marched on Odani Castle, and the combined force Azai-Asakura marched out to confront Nobunaga. Nobunaga reacted and advanced to the southern bank of the Anegawa. The following morning on July 30, 1570 the battle between Oda and the Azai-Asakura forces began. Tokugawa Ieyasu joined his forces with Nobunaga, with the Oda and Azai clashing on the right while Tokugawa and Asakura grappled to the left. The battle turned into a melee fought in the middle of the shallow Ane River. For a time, Nobunaga’s forces fought the Azai upstream, while the Tokugawa warriors fought the Asakura downstream. After the Tokugawa forces finished off the Asakura, they turned and hit the Azai right flank. Inaba Ittetsu, who had been held in reserve, then came forward and hit the Azai left flank. Soon Oda-Tokugawa forces defeated the combined forces of the Asakura and Azai clans.

Nobunaga faced a significant threat from the Ikkō-ikki, a resistance movement centered around the Jōdo Shinshū sect of Buddhism. The Ikkō-ikki began as a religious association for self-defence, but popular antipathy against the samurai from the constant violence of the Sengoku period caused their numbers to swell. By the time of Nobunaga’s rise to power, the Ikkō-ikki was a major organized armed force opposed to samurai rule in Japan. In August 1570, Nobunaga began a campaign against the Ikkō-ikki while fighting against his samurai rivals. In May 1571, Nobunaga besieged Nagashima, a series of Ikkō-ikki fortifications in Owari Province, beginning the Sieges of Nagashima.

In the meantime, the Enryaku-ji monastery on Mt. Hiei, with its sōhei (warrior monks) of the Tendai school who aided the anti-Nobunaga group by helping the Azai-Asakura alliance, was an issue for Nobunaga since the monastery was so close to his base of power. In September 1571, Nobunaga preemptively attacked the Enryaku-ji monastery, he besieged Mount Hiei and razed it. In the process of making their way to the Enryaku-ji temple, Nobunaga’s forces destroyed and burnt all buildings, killing monks, laymen, women, children and eliminating anyone who had previously escaped their attack. “The whole mountainside was a great slaughterhouse and the sight was one of unbearable horror.” This action, gained him renown as the “Demon Daimyo” or “Devil King”.

One of the strongest rulers in the anti-Nobunaga alliance was Takeda Shingen, in spite of his generally peaceful relationship and a nominal alliance with the Oda clan. At the apex of the anti-Nobunaga coalition, in 1572, Takeda Shingen ordered Akiyama Nobutomo, one of the “Twenty-Four Generals” of Shingen, to attack the Iwamura castle. Nobunaga’s aunt, Lady Otsuya, conspired against the Oda clan, surrendered the castle to the Takeda and married Nobutomo. From there, the Takeda-Oda relationship declined and Nobunaga started a campaign against the Takeda clan.

In 1573, at the Siege of Odani Castle and the Siege of Ichijōdani Castle, Nobunaga successfully destroyed the Asakura and Azai clans by driving them both to the point that the clan leaders committed suicide.

Nobunaga’s first siege of Nagashima ended in failure, as his trusted general Shibata Katsuie was severely wounded and many of his samurai were lost before retreating. Despite this defeat, Nobunaga was inspired to launch another siege after the success of the Siege of Mount Hiei. In July 1573, Nobunaga besieged Nagashima for a second time, personally leading a sizable force with many arquebusiers. However, a rainstorm rendered his arquebuses inoperable while the Ikkō-ikki’s own arquebusiers could fire from covered positions. Nobunaga himself was almost killed and forced to retreat, with the second siege being considered his greatest defeat.

In the same year, Shingen decided to make a drive for Kyoto at the urgings of the shōgun Ashikaga Yoshiaki, starting with invading Tokugawa territory. Nobunaga, tied down on the western front, sent lackluster aid to Tokugawa Ieyasu who suffered defeat at the Battle of Mikatagahara in 1573. However, after the battle, Tokugawa’s forces launched night raids and convinced Takeda of an imminent counter-attack, thus saving the vulnerable Tokugawa with the bluff. This would play a pivotal role in Tokugawa’s philosophy of strategic patience in his campaigns with Nobunaga. Shortly thereafter, the Takeda forces were neutralized after Shingen died in April 1573.

After the death of Takeda Shingen, Nobunaga’s entry into Kyôto presented him with a situation very different from that which he had come. He focused on Ashikaga Yoshiaki, who had openly declared hostility more than once, despite the Imperial Court’s intervention. Nobunaga was able to defeat Yoshiaki’s forces, and the power of the Ashikaga was effectively destroyed on August 27, 1573, when Nobunaga drove Yoshiaki out of Kyoto and sent him into exile. Yoshiaki became a Buddhist monk, shaving his head and taking the name Sho-san, which he later changed to Rei-o In, bringing the Ashikaga Shogunate to an end.

In 1574, Nobunaga launched a third siege of Nagashima as his general Kuki Yoshitaka began a naval blockade and bombardment of Nagashima, allowing him to capture the outer forts of Nakae and Yanagashima as well as part of the Nagashima complex. The Sieges of Nagashima finally ended when Nobunaga’s men completely surrounded the complex and set fire to it, killing the remaining tens of thousands of defenders and inflicting tremendous losses to the Ikkō-ikki.

In early 1574, Nobunaga was promoted to the ‘Junior third rank’ (Ju Sanmi) and made a ‘Court advisor’ (Sangi). Court appointments would continue to be lavished on a nearly annual basis, possibly in hope of placating him. Nobunaga acquired many official titles, including ‘Major Counselor’ (Gondainagon), Ukon’etaishō, and ‘Minister of the Right’ (Udaijin) in 1576. In February 1578 the court made him ‘Grand Minister of State’ (Daijo daijin), the highest post that could be given.

In 1575, Takeda Katsuyori, son of Takeda Shingen, attacked Nagashino Castle when Okudaira Sadamasa rejoined the Tokugawa and his original plot with Oga Yashiro to take Okazaki Castle, the capital of Mikawa, was discovered. Ieyasu appealed to Nobunaga for help and Nobunaga personally lead an army of about 30,000 men. The combined force of 38,000 men under Nobunaga and Tokugawa Ieyasu defeated and devastated the Takeda clan with the strategic use of arquebuses at the decisive battle in Nagashino, Mikawa Province. Nobunaga compensated for the arquebus’ slow reloading time by organizing the arquebusiers in three rows, firing in rotation.

Additionally, Nobunaga was very interested in European culture which was still very new to Japan. He collected pieces of Western art as well as arms and armor, and he is considered to be among the first Japanese people in recorded history to wear European clothes. He also became the patron of the Jesuit missionaries in Japan and supported the establishment of the first Christian church in Kyoto in 1576, although he never converted to Christianity.

Simultaneously, Nobunaga had been besieging the Ikkō-ikki’s main stronghold at Ishiyama Hongan-ji in present-day Osaka. Nobunaga’s Siege of Ishiyama Hongan-ji began to slowly make some progress, but the Mōri clan of the Chūgoku region broke his naval blockade and started sending supplies into the strongly fortified complex by sea. As a result, in 1577, Hashiba Hideyoshi was ordered by Nobunaga to confront the warrior monks at Negoroji, and Nobunaga eventually blocked the Mōri’s supply lines.

The Tedorigawa Campaign was precipitated by Uesugi intervention in the domain of the Hatakeyama clan in Noto Province, an Oda client state. This event provoked the Uesugi incursion, a coup d’état led by the pro-Oda General Chō Shigetsura, who killed Hatakeyama Yoshinori, the lord of Noto and replaced him with Hatakeyama Yoshitaka as a puppet ruler. As a result, Uesugi Kenshin, the head of the Uesugi clan, mobilized an army and led it into Noto against Shigetsura. Consequently, Nobunaga sent an army led by Shibata Katsuie and some of his most experienced generals to attack Kenshin. They clashed at the Battle of Tedorigawa in Kaga Province in November 1577. The result was a decisive Uesugi victory, and Nobunaga considered ceding the northern provinces to Kenshin, but Kenshin’s sudden death in early 1578 caused a succession crisis that ended the Uesugi’s movement to the south.

In 1580, ten years after the siege of Ishiyama Hongan-ji began, the son of Chief Abbot Kōsa surrendered the fortress to Nobunaga after their supplies were exhausted, and they received an official request from the Emperor to do so. Nobunaga spared the lives of Ishiyama Hongan-ji’s defenders, but expelled them from Osaka and burnt the fortress to the ground. Although the Ikkō-ikki continued to make a last stand in Kaga Province, Nobunaga’s capture of Ishiyama Hongan-ji crippled them as a major militant force.

Tenshō Iga War (天正伊賀の乱, Tenshō Iga no Ran) were two invasions of Iga province by the Oda clan during the Sengoku period. The province was conquered by Oda Nobunaga in 1581 after an unsuccessful attempt in 1579 by his son Oda Nobukatsu. The names of the wars are derived from the Tenshō era name (1573–92) in which they occurred. Other names for the campaign include “The Attack on Iga” (伊賀攻め, Iga-zeme) or “Pacification of Iga” (伊賀平定, Iga Heitei). Oda Nobunaga himself toured the conquered province in early November 1581, and then withdrew his troops, placing control in Nobukatsu’s hands.

From there, Nobunaga continued his expansion, sending Akechi Mitsuhide to pacify Tanba Province and Hashiba Hideyoshi to Himeji Castle, before advancing upon the Mori clan in Nagato Province. The end of the Takeda clan came in 1582, when Oda-Tokugawa forces conquered Kai Province. Takeda Katsuyori was defeated at the Battle of Tenmokuzan and then committed seppuku.

By 1582, Nobunaga was at the height of his power and, as the most powerful warlord, the de facto leader of Japan. Nobunaga and Ieyasu finally defeated the Takeda at the Battle of Tenmokuzan, destroying the clan and resulting in Takeda Katsuyori fleeing from the battle before committing suicide with his wife while being pursued by Oda forces. By this point, Nobunaga was preparing to launch invasions into Echigo Province and Shikoku. Nobunaga’s former sandal bearer, Hashiba Hideyoshi, invaded Bitchū Province and laid siege to Takamatsu Castle. The castle was vital to the Mori clan, and losing it would have left the Mori’s home domain vulnerable. Mori reinforcements led by Mōri Terumoto arrived to relieve the siege, prompting Hideyoshi to ask for reinforcements from Nobunaga, who promptly ordered his leading generals to prepare their armies, with the overall expedition to be led by Nobunaga. Nobunaga left Azuchi Castle for Honnō-ji, a temple in Kyoto he frequented when visiting the city, where he was to hold a tea ceremony. Hence, Nobunaga only had 30 pages with him, while his son Oda Nobutada had brought 2000 of his cavalrymen.

Akechi Mitsuhide, stationed in the Chūgoku region, decided to assassinate Nobunaga for unknown reasons, and the cause of his betrayal is controversial. Mitsuhide, aware that Nobunaga was nearby and unprotected for his tea ceremony, saw an opportunity to act. Mitsuhide led his army toward Kyoto under the pretense of following the order of Nobunaga, but as they were crossing Katsura River, Mitsuhide announced to his troops that “The enemy awaits at Honnō-ji!” (敵は本能寺にあり, Teki wa Honnō-ji ni ari). On 21 June 1582, before dawn, the Akechi army surrounded the Honnō-ji temple with Nobunaga present, while another unit of Akechi troops were sent to Myōkaku-ji in a coup. Although Nobunaga and his servants resisted the unexpected intrusion, they were soon overwhelmed. As the Akechi troops closed in, Nobunaga decided to commit seppuku in one of the inner rooms. Reportedly his last words were, “Ran, don’t let them come in…” referring to his young page, Mori Ranmaru, who set the temple on fire as Nobunaga requested so that no one would be able to get his decapitated head. Ranmaru then followed his lord, with his loyalty and devotion makes him a revered figure in Japanese history. Nobunaga’s remains were never found, a fact often speculated about by writers and historians. After capturing Honnō-ji, Mitsuhide attacked Nobutada, eldest son and heir of Nobunaga, who also committed suicide.

Following the incident, Mitsuhide declared himself master over Nobunaga’s domains, but was quickly defeated by Toyotomi Hideyoshi, who regained control of and greatly expanded the Oda holdings. Nobunaga’s successful subjugation of much of Honshu enabled the later successes of his allies Hideyoshi and Tokugawa Ieyasu toward the goal of national unification by subjugating local daimyōs under a hereditary shogunate, which was ultimately accomplished in 1603 when Ieyasu was granted the title of shōgun by Emperor Go-Yōzei following the successful Sekigahara Campaign of 1600. The nature of the succession of power through the three daimyōs is reflected in a well-known Japanese idiom:

Nobunaga has also been portrayed fictively, such as when the figure of Nobunaga influences a story or inspires a characterization. In James Clavell’s novel Shōgun, the character Goroda is a pastiche of Nobunaga. In the film Sengoku Jieitai 1549, Nobunaga is killed by time-travellers. The novel and anime series Yōtōden, the novel The Ouka Ninja Scrolls: Basilisk New Chapter and the anime and manga Basilisk portray Nobunaga as a literal demon in addition to a power-mad warlord. Nobunaga also appears as a major character in the eroge Sengoku Rance and is a playable character in Pokémon Conquest, with his partner Pokémon being Hydreigon, Rayquaza and Zekrom. Nobunaga is depicted as a female character in the anime Sengoku Otome: Momoiro Paradox, Sengoku Collection, the video game Fate/Grand Order, and in the light novel and anime series The Ambition of Oda Nobuna. He is the main character of the stage action and anime adaptation of Nobunaga the Fool. In Kouta Hirano’s Drifters, Nobunaga is rescued before the moment of his death and is sent to another world to fight against other historical figures. Therein, he displays equal parts tactical brilliance and gleeful brutality. In the 2014 anime Nobunaga Concerto, and its 2015 film adaptation, he is the subject of a complex plot involving time travel and alternate history.