The Battle of Ishiyama (石山合戦, Ishiyama Kassen) is the decade long siege Nobunaga conducted against the Ikkō Ikki. These ind In the aftermath of Nobunaga entering Kyoto to restore the shogunate, the Ikko-ikki and other monk sects such as the Enryaku-ji and Saika-ikki joined the clans rising up against Nobunaga in an anti-Nobunaga coalition. Ishiyama-Honganji was their main citadel, their rallying point that Nobunaga sought to destroy for 10 years, with several very costly battles fought in the attempts to capture said fortress. When the castle finally fell, Nobunaga chose to spare most of the populace, sufficing himself with the citadel's complete destruction. Hideyoshi Toyotomi would later use the favorable site to build his own castle, Ōsaka Castle.
Role in Games
Samurai Warriors 2 only alludes to the ongoing siege of Ishiyama Honganji during the battle of Osaka Bay. The rest of the series ignores this campaign of Nobunaga's conflict with the Ikko-Ikki. Often its participants are lumped in with the Mōri clan.
It is in Samurai Warriors: Spirit of Sanada that Ishiyama first appears as a proper battle. It is one of the secondary battlefields in chapter 4. The battle is from the Ikko-Ikki's side of the conflict, led by Magoichi Saika, with Takakage Kobayakawa present as Mōri reinforcements and Hisahide Matsunaga joining as part of the resistance to Oda rule. The battle begins with the Ishiyama defenders split between the north and south, trying to fight their way to the Oda main camp before reinforcements can reach them. Narimasa Sassa and Tsuneoki Ikeda attempt to rush the defenders before they can gather for their attack and require being defeated quickly. When Magoichi orders the charge towards the center Oda main camp, Mitsuhide Akechi and Gracia appear and block the way, trying to foil the anti-Nobunaga force's plan. Hanbei Takenaka and Kanbei Kuroda act as the camp's leaders and once engaged, Nobunaga himself arrives with several Iron Warships to bombard the defenders and take control of his army.
Magoichi can order his marksmen to snipe the cannoneers if a Sanada coin is used, which temporarily stops the cannon fire. Takakage orders his Mōri forces to arrive, but instead Hideyoshi appears at the dock, blocking their landing until he's defeated. Nene also appears with many kunoichi, causing chaos across the battlefield until she's defeated. Yoritaka Hachiya defends the Oda's docks to the Iron Warships, and when defeated, Nō and Ranmaru Mori appear to try and keep their ships from falling to the Ikko-Ikki's assault. Once captured, defeating Nobunaga wins the battle.
Historical Information
The Ikko-Ikki had little interaction with Oda Nobunaga until after the Oda warlord helped reestablish the Ashikaga Shogunate by placing Ashikaga Yoshiaki as the 15th Ashikaga Shogun in 1568. Kennyo quickly grew to dislike Nobunaga, as the warlord started reinforcing the different tax requirements that the Buddhist ministries hadn't been required to pay in decades. This tension rose as Nobunaga subjugated the Miyoshi, as they were neighbors of the Ikko-Ikki. When Nobunaga expelled Yoshiaki from the Shogunate, Kennyo chose to send a sword and message to Ishiyama Honganji, telling them that Nobunaga intended to destroy their temple.
As a result of such a message, the Ikko-Ikki rallied and attacked Nobunaga's forces at Yodogawa in Settsu. The Oda forces were able to handily repel the peasant forces, but unable to press their victory, as they were still engaged in the Siege of Shiga. Nobunaga had to content himself with placing Ishiyama under surveillance to give warning should they move out of their fortress again. The next four years saw a sort of cold war set in between the two factions, with Takeda Shigen, who's wife was Kennyo's wife's sister, attempt to negotiate peace (while secretly creating an alliance with the Ikko-Ikki and Mōri).
This cold war ended when Nobunaga's governor of Echizen, Maeba Yoshitsugu, lost the province and Koga province to an Ikko-Ikki rebellion due to his harsh treatment of the populace. Kennyo was quick to unite with these northern Ikki, putting himself in active war with the Oda. Nobunaga responded with fury, destroying and retaking his lands except for Ishiyama itself. Kennyo was temporary scared into peace talks after the annihilation of Nagashima.
The uneasy peace lasted only two years before Kennyo rejoined the struggle against the Oda. In 1576, they began attacking the nearby Oda lands and Nobunaga sent a force under Akechi Mitsuhide. The Ikko-Ikki forces were able to keep their ports open and use these constant supplies to sally out and soundly defeat Mitsuhide's army. With his forces spread out fighting on multiple fronts, Oda Nobunaga gathered the troops near himself, roughly 3,000 men, and attacked the 15,000 men sieging Mitsuhide in his fort. Mitsuhide saw the reinforcements and sallied out as well and the two forces forced the Ikko-Ikki back into Ishiyama (called the battle of Tennoji).
After these battles, Nobunaga tightened his siege of Ishiyama, trying to cut off their access to their ports as well. As a result, the two battles of Kizugawa, the first battle being fought shortly afterwards and ending in complete failure for the Oda. The first navel conflict forced the siege back to a three-sided siege, leaving the sea wide open for much needed supplies. The Ikko-Ikki's position weakened in 1577 when Nobunaga successfully suppressed the Saika forces in Kii. However, the following year Araki Murashige rebelled and set the siege back once more, as he was one of the main commanders over the siege of the fortress.
By 1579 though, Nobunaga had once more reversed his fortunes. The second battle of Kizugawa had been fought and Nobunaga's iron-plated ships had destroyed the Mōri forces. This ended the supply trains to Ishiyama, including the essential supply of bullets. Murashige had also been defeated, strengthening the siege against the castle to a complete encirclement. Kennyo began seeking a way to negotiate a peaceful conclusion, but had to wait for the Mōri's power to weaken in the imperial court before they could violate their alliance and surrender. In 1580, the Ikko-Ikki surrendered peacefully, the cost mostly being the complete destruction of the mountain temple fortress. A few years later, in 1583, Hashiba Hideyoshi began construction of his own castle on the same site, recognizing the location's strategic value.