"Brutal", "fanatical", "militant", and "sack-cleavingly homicidal" aren't descriptors that are typically attached to our understanding of Buddhism, a holistic set of gluten-free organic free-range spiritual beliefs that by-and-large preach a bunch of one-with-the-universe hippy shit like meditating on the nature of existence, contemplating water as it courses through a quiet stream in a bunny-filled meadow, and generally not ripping your enemies apart limb-by-limb with the razor-sharp blade of a Japanese halberd and then using their gibbed-apart corpses as target practice for your badass corps of arquebus-toting riflemen.
That's because not enough people know the story of Kennyo Kosa, the Eleventh Abbot of Ishiyama Hongan-ji, and how his fanatical, militant, sack-cleavingly homicidal Buddhist warriors rocked out an epic, bullet-riddled ten-year resistance to the rule of the infamous Japanese feudal lord Oda Nobunaga that resulted in roughly three-quarters of the Osaka countryside being redecorated with dismembered appendages, fractured skulls, and high-impact samurai blood spatter all over the place like what the fuck.
So while we generally don't like think of Buddhists as being overly-zealous about anything more intense than militant veganism, excessive abuse of incense, and an uncontrollable urge to own a hybrid automobile, Kennyo Kosa was the awe-inspiring leader of a militant sect of ball-crunching Buddhist warrior-monks that put a distinctly 16th-century Japanese spin on the Five Noble Truths, trading in mundane boring shit like zen karma pseudo-Transcendentalist serenity with nature for a bloody katana blade and an overwhelming belief that death in battle for the Buddha brought instant salvation and any display of cowardice in combat was a decent cause for the earth to open up under your feet and swallow you straight into hell. Which is kind of awesome.
Founded in 1457 in Kaga Prefecture, this "True Pure Land" sect of Buddhism was also pretty bitchin' in that the basic idea behind it was that your typical feudal Japanese peasant's life – which for the most part consisted of growing rice, cooking the rice, eating it, and then immediately being stabbed in the throat by a rampaging samurai who was currently in the process of torching your village into ash and carrying your wife off to be his concubine – really wasn't all that great, and that a big reason for that was because samurai were a bunch of gigantic fucking assholes. So, in 1488, this association of pissed-off farmers, monks, merchants, carpenters, scholars, and other non-samurai-types got super ripshit pissed, grabbed their pitchforks, torches, and homemade bear traps, overthrew the samurai leaders of Kaga Prefecture with a massive revolt, set up a civilian, non-samurai prefectural government for the first time in Japanese History, and then proceeded to administrate it like civilized human beings for the next hundred or so years. It was actually pretty great, right up until the samurai eventually decided they'd had enough of this bullshit and they were going to remind everyone who was boss.
When Kennyo Kosa took over as the 11th Abbot in 1554, he was basically walking face-first into a gigantic whirlwind shitstorm of Japanese history, one that was essentially personified in the character of the "Demon King" Oda Nobunaga – a future badass of the week in his own right and hands-down one of the most ridiculously hardcore human beings who ever lived.
Oh, and if you've never heard of Nobunaga before, and the potentially-too-subtle "He's the Fucking Demon King" thing doesn't tip you off as to what his business was all about, here's an example of how he's generally portrayed in basically every piece of semi-historical Japanese artwork out there:
Nice Dudes from History generally aren't portrayed in black plate armor with sinister 'stache's holding gigantic glowing swords while overlooking a burning inferno that at one point had to have been a major metropolitan area. This was a man who made it his life goal to crush all of Japan under his iron-plated fist. A man who once met with a bunch of Christian missionaries and the only thing he took away from it was that you could kill a guy by nailing him to a tree – and from that point on became infamous for crucifying enemy prisoners of war. He was a man who didn't have much need for warrior-monks telling peasants that they don't have to pay taxes or listen to samurai, and no fucking bullshit hippy commune utopia noise was going to stop him from his badass quest for rampaging glory.
But while Nobunaga had little trouble cleaving his way through the Japanese countryside in a swirling steel inferno of human blood, he failed to realize exactly who he was fucking with when, in early 1570, he marched a massive army of 30,000 men out to lay siege to the capital of the "True Pure Land" sect – for fortress known as Ishiyama Hongan-ji in present-day Osaka.
Musket-wielding Japanese warrior-monks.
Commanded by the utterly-fearless, diplomatically-brilliant Abbott Kennyo Kosa, Ishiyama Hongan-ji was an ultra-modern fortress city that had been a center of commerce and learning for decades and was home to roughly fifteen thousand hardcore, fanatical, naginata- and musket-slinging badasses with nothing to lose. In addition to having a Klingon-style belief in combat-related martyrdom, these guys damn well knew that even if they surrendered they were going to end up tasting the pointy end of a katana (when Nobunaga destroyed the monastery on Mt. Hiei he gave the monks two choices – jump into a fire or have a sword rammed down your throat), and at Kosa's urging they all swore to fight Nobunaga with their last breath and to never allow their monastery to fall to the invading samurai armies.
They were pretty well set up for the task, too. Built on an old Imperial Palace, Ishiyama Hongan-ji was a sophisticated series of sturdy stone walls, fortresses, and easily-defensible structures positioned along the slopes of an ultra-steep hill, with moats and creeks blocking the approach and a sheer cliff face dropping off to the ocean guarding the back of the fortress. If it's not enough that the final approach to the citadel required Nobunaga's men to charge uphill through uneven terrain across open ground while the defenders fired muskets and arrows at them, the Ishiyama Hongan-ji was further surrounded by a network of over 50 watchtowers and guardhouses, plus Kennyo Kosa also managed to have his men booby-trap the entire area with tripwires and clay pots specially designed to break the ankles of enemy warriors and horses, and set up a system of bells and signal fires that allowed him to summon 10,000 of his best warriors to any part of the Branch Davidian Compound within minutes. Thanks to a clever alliance with the nearby Mori Clan, who were masters of naval strategy and combat, Kennyo Kosa ensured that his people were resupplied with bullets, food, and medical supplies by sea, leaving him free to turn the entire mountain slope into one gigantic hellacious deathtrap without worrying about how the hell he was going to get supplies through the 30,000 Oda Clan samurai that now encircled his city by land.
The main complex, c. 1574.
Nobunaga ordered the attack. He marched out with tens of thousands of hardened warriors, grizzled from decades of combat against some of Japan's toughest warlords, expecting to crush this peasant army under his heel like a C-130 transport aircraft landing wheels-down on a week-old banana.
What he ran in to were fifteen thousand fanatical gunslinging monks, pissed-off peasants, spear-swinging Shinto priests, and badass katana-equipped Ronin warriors, all charging screaming towards them carrying a bowel-weakening assortment of deadly weaponry and displaying banners with Buddhists sayings scrawled on them in human blood. They charged forward for their religion, fighting for their own lives, and for their leader, Kennyo Kosa, a man who was believed to hold the power over who went to Heaven or Hell and who could condemn a man to eternal damnation if he hesitated in battle. Every last man fought to death, never once thinking of retreat or surrender. Psychotic zealots with nothing to lose.
Nobunaga's attack was repulsed with massive losses. Then, as he was regrouping, Kosa's gunners launched night attacks to harass their camp, torch their siege structures, and instill fear in the men. Then, just to show the Demon King exactly how much he thought of him, Kennyo Kosa mobilized True Pure Land believers in other provinces to rise up and fight alongside any nobles willing to oppose Nobunaga – including one case in late 1570 when some of his men besieged Nobunaga's brother's house and forced him to seppuku himself to death. This ability to mobilize forces all throughout the country helped Kosa initiate some powerful alliances with other regional lords, many of whom agreed to attack Nobunaga to help take some of the heat off the siege of Ishiyama Hongan-ji Castle.
For the next four years (!), Nobunaga failed to make any progress. Harassed on all sides by enemies, he couldn't put enough troops out to break through Ishiyama Hongan-ji's defenses, but he also couldn't lift the siege because every time he turned around the monks trashed his forts and caused all kinds of trouble. In 1574, bitter and angry and his repeated failed attempts to take the castle, Nobunaga took on a different strategy, this time attacking outlying cities and anyone who was supporting Kennyo Kosa's forces. In once city he forced everyone indoors, set the entire place on fire, then had his men shoot anyone who came out of their homes. A few months after that he attacked a different city and wiped out so many people that, as he wrote in his memoirs, "You like seriously couldn't take a leak without pissing on a corpse… dude, it was TOTALLY hilarious you shoulda been there bro LOL."
Ah, good times.
After crushing the surrounding resistance, Nobunaga then attempted to blockade the seaport, attacking the Mori Clan ships that were ferrying supplies to the beleaguered defenders. The Mori, however, were masters of naval combat, and in a major battle in 1576 they destroyed Nobunaga's attempt to stop them from pissing him off. When this failed, he sent his best general – Akechi Mitsuhide – to launch a full-scale assault with 10,000 heavily-armored samurai warriors, but they were bitch-slapped back down the hill by a throng of 15,000 gun-toting monks. Nobunaga, pissed off that he had to do everything himself, then personally led his army in yet another assault, and not only got thrown back out on his ass, but somehow ended up catching a bullet and getting wounded in combat in the process.
Well despite all of Kosa's tenacity and his troops' unwillingness to surrender, shit got bad in 1578 when Nobunaga rolled into the harbor with a bunch of psycho iron-clad battleships that proceeded to completely fuck up the Mori fleet like you could not imagine. Nobunaga then blockaded the port, preventing Kosa from resupplying, and the Abbott's calls for help and assistance all went unheeded on account of the fact that Nobunaga pretty much already killed every single person who could possibly have helped him.
Still, Kosa refused to surrender. With the walls crumbling beneath him, enemy troops attacking on a daily basis, and his food and ammunition supplies dwindling by the hour, Kosa and the Ishiyami Hongan-ji held out for an incredible two more years, despite having zero support from anyone else in Japan. Nobunaga intensified his attack, concentrating 60,000 soldiers – the bulk of his army – on utterly annihilating the warrior-monks, but Kosa's men continued to fight like savage demons, firing until the barrels of their muskets turned red and their swords were smashed into more shards than a Triforce.
Finally, after ten years – the longest siege in Japanese history – and tens of thousands of lives, Nobunaga made one final appeal. He went to the Emperor himself, and asked His Imperial Majesty to write Kosa a letter begging him to surrender. Despite the obvious coercion involved, this was something that not even the ultra-devout Kennyo Kosa could ignore. He saw the letter, recognized his lost situation, signed the Imperial Decree with his own blood, and ordered his monks to burn the entire Ishiyami Hongan-ji complex to the ground to prevent Nobunaga from being able to claim it. In a ridiculously-rare display of badass-to-badass appreciation, Nobunaga allowed Kosa and his followers to walk out of there alive.
Oh, and then, because it had fucked him up so bad and given him the biggest fight of his career, Nobunaga ordered a castle be built on the ruins of the city. The site would end up becoming Osaka Castle, one of the most famous fortresses in Japanese history.
Kennyo Kosa, meanwhile, still wasn't done. He took his followers south, to friendly lands, and started helping Nobunaga's eventual successor, Toyotomi Hideyoshi, providing his monks as irregular combat troops against the enemies of the Shogun. For his loyalty, Hideyoshi rewarded the Abbott in 1591 by allowing him to build a new temple, this time in Kyoto. Today the Nishi Hongan-ji (literally "Western Temple of the Original Vow," though nowadays it's just known as "Dear Mr. West") is a UNESCO World Heritage Site.
Kennyo Kosa died a year later of natural causes, passing leadership of the sect to his sons.
Sengoku Field Manual
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