Battle of Okehazama

In June 1560, in Owari Province in central Japan, the young warlord Oda Nobunaga launched a surprise attack on the camp of a far larger invading army and killed its commander, Imagawa Yoshimoto. The victory at Okehazama, near present-day Nagoya, saved the Oda clan from destruction and lifted Nobunaga from a provincial lord into one of the leading contenders for power in the Sengoku period, the age of warring states.

By 1560 Imagawa Yoshimoto ruled the provinces of Suruga, Tōtōmi and Mikawa along Japan's Pacific coast. He gathered an army of about 25,000 men and set off along the Tōkaidō highway towards Kyoto, where the Ashikaga shogunate had grown feeble. His route led through Owari, which Nobunaga had only recently brought under his control.

The invaders made swift progress. They captured the Oda border fort of Washizu, while a contingent of the Matsudaira clan, allies of the Imagawa led by Matsudaira Motoyasu, took the fort of Marune. Yoshimoto then pitched camp in a narrow valley called Dengaku-hazama, at the village of Okehazama.

Nobunaga could muster only some 2,000 to 3,000 men, roughly a tenth of the enemy's strength. Some of his advisers urged him to shelter in Kiyosu Castle, but he judged that it could not survive a siege and decided that only an attack offered any chance. He knew the ground well, because his men had used it for exercises disguised as falconry hunts. According to tradition, before setting out he recited lines from the song Atsumori about the brevity of human life.

He marched from Kiyosu by way of Atsuta Shrine to the fortified temple of Zenshō-ji, close to Okehazama, where he had banners and flags set up to make his small force look much larger to enemy scouts.

What exactly happened next is clouded by legend. The traditional story has the Oda force slipping round to attack the Imagawa camp from the north, but many modern historians think it was more likely a direct frontal assault, whether planned or not. Either way, the Imagawa were taken completely by surprise. Celebrating their easy successes on a hot afternoon, many had taken off their armour. A thunderstorm hid the Oda advance, and when the blow fell on the centre of the camp, panic spread and men broke and ran.

Yoshimoto at first seems to have thought the noise was his own men carousing. He and his guards left the camp and were drawn into the fighting nearby. He is said to have wounded one attacker, Mōri Shinsuke, before another Oda samurai, Hattori Koheita, overpowered him and took his head. With Yoshimoto and nearly all his senior officers dead, the rest of the army surrendered or scattered.

The battle is counted among the great turning points of Japanese history. The Imagawa clan never recovered and was soon swallowed up by its neighbours, while Nobunaga's reputation soared and many warriors and lesser lords came over to him. Among them was Matsudaira Motoyasu, who had fought on the Imagawa side and later became Tokugawa Ieyasu. Okehazama is also remembered as the occasion when Nobunaga first took note of a humble sandal-bearer who would rise to become Toyotomi Hideyoshi, the next unifier of the country.

The battlefield, now a park in the city of Toyoake, was designated a National Historic Site in 1937.

Our 1530 map shows Japan in the years of division before Okehazama, and our 1600 map shows the country after the wars of unification that Nobunaga began.