[a][3][8] However, there is no doubt that matchlock guns played an active role, including in the sniping death of Yamagata Masakage, who was a famous general in the Takeda Army.

Ieyasu's position was that of a subcontractor who could not complain, although he called himself a cooperative company, and was used by Nobunaga as a good bulwark against the powerful Takeda forces.

He then moved south along the Toyokawa River and ravaged the entire East Mikawa region, launching raids throughout the Tokugawa vassals' estates.

[7][17] Katsuyori surrounded Nagashino Castle, which had only 500 defenders, with a large army of 15,000 men and launched an onslaught to make it a bridgehead for the Mikawa invasion.

However, he had just rested his soldiers after the battle had been brought to a halt when he attacked a castle built by the Hongan-ji and the Miyoshi clan offered to surrender.

[17][18][19] Meanwhile, at Nagashino Castle, which was on the verge of falling under the onslaught of the Takeda forces, Torii Suneemon was sent as a messenger to Ieyasu in Okazaki to ask for reinforcements.

Informed that Ieyasu was marching on Nagashino with the Oda forces, Torii returned to the castle to deliver the good news.

[5][8][21] When Takeda's vassals learnt of the arrival of Oda's army, they advised Katsuyori to retreat to Kai, but he decided to go ahead with the decisive battle.

[18] On 28 June, Takeda Katsuyori marched to the east of Shitaragahara with his main force of 12,000, leaving 3,000 men to maintain the siege around Nagashino Castle.

Nobunaga adopted a suggestion from Sakai Tadatsugu, a Tokugawa vassal, and ordered a surprise attack on Mount Tobigasu.

[8][10][18] On the early morning of 29 June, Tadatsugu launched an attack against the Takeda forces defending the fort from behind Mount Tobigasu.

[18] After receiving the report about the battle's development, Nobunaga personally came to Mount Takamatsu, Ieyasu's main camp, to inspect the war situation and took command of the entire army there.

[18] Takeda's forces repeatedly charged, but each time they were blocked by matchlock guns and horse defense fences, and retreated.

[8] With many of their troops killed, Takeda's army began to retreat, but Nobunaga pounced on them when their ranks gave way, inflicting even more casualties.

[19] The battle ended in an overwhelming victory for the allied forces, with the Takeda side losing a number of well-known commanders.

Several of the Twenty-Four Generals of Takeda Shingen were killed in this battle, including Baba Nobuharu, Hara Masatane, Sanada Nobutsuna with his younger brother Sanada Masateru, Yamagata Masakage, Saegusa Moritomo, Tsuchiya Masatsugu, Naitō Masatoyo, and Obata Masamori who received a mortal wound.

Moreover, a myth was created that Nobunaga was a military genius who devised a new battle strategy called 'three-stage shooting', in which the shooters took turns one after the other.

It has been claimed that Nobunaga invented this tactic to compensate for the shortcomings of matchlock guns, which takes time to reload, and enabled uninterrupted, continuous firing.

[22][23] The original source for this theory was Nihon Senshi Nagashino no Eki (Japanese Military History: Battle of Nagashino, 1903), compiled by the Imperial Japanese Army General Staff Office based on the war tales Shinchōki[c] written by Oze Hoan, a Confucian scholar of the Edo period.

Sohō praises the 'horse defense fence' and 'three-stage shooting' and states that the Shingen style of warfare is regrettable because it is outdated compared to Nobunaga's innovative tactics.

Subsequently, doubts were raised and research was reviewed, resulting in the prevailing opinion that the three-stage shooting by the Oda-Tokugawa allied forces with 3,000 matchlock guns was a later invention.

[22] According to Shinchō Kōki,[b] Nobunaga deployed about 1,000 matchlock guns between five commanders – Sassa Narimasa, Maeda Toshiie, Nonomura Masanari, Fukuzumi Hidekatsu and Ban Naomasa – and had the ashigaru press the enemy close.

The lead in the shot of the Oda-Tokugawa allied forces was classified into three types: domestic, South China and Korea, and Thailand.

[27] Meanwhile on more global perspective, professor Tatsuo Fujita viewed the Nagashino battle was an indicator of the Portuguese Empire ambition to make Japan as their colony through their Jesuit missionaries and merchant to gain favor of the prospective future benefactor, Oda Nobunaga.