Mas Oyama and the Birth of Kyokushin Karate

• Introduction
• Chapter 1 The Roots of Choi Yeong-eui
• Chapter 2 Crossing the Sea to Wartime Japan
• Chapter 3 Under the Shadow of the Rising Sun: The Aviation Academy Years
• Chapter 4 Early Masters: Shotokan and Goju-ryu Foundations
• Chapter 5 Surviving the Ashes: Tokyo in the Immediate Post-War Era
• Chapter 6 The Influence of Eiji Yoshikawa's Musashi
• Chapter 7 Retreat to Mount Minobu: The First Mountain Solitude
• Chapter 8 Forging the Iron Body: The Rigors of Mount Kiyosumi
• Chapter 9 The Return to Civilization and the 1947 All-Japan Championship
• Chapter 10 Taming the Beast: The Legend of the Bull Fights
• Chapter 11 The American Odyssey: Pro Wrestling, Challenges, and the "Godhand"
• Chapter 12 The Birth of the Oyama Dojo in Mejiro
• Chapter 13 Rejecting Non-Contact: The Quest for Absolute Realism
• Chapter 14 The Naming of Kyokushin: The Search for the Ultimate Truth
• Chapter 15 The Bangkok Challenge: Muay Thai vs. Karate
• Chapter 16 Establishing the Honbu: Ikebukuro and the Global Vision
• Chapter 17 The Ordeal of Spirit: Creation of the 100-Man Kumite
• Chapter 18 Karate Baka Ichidai: Pop Culture and the Kyokushin Boom
• Chapter 19 The 1975 First World Open: A New Era of Full-Contact Martial Arts
• Chapter 20 Expanding the Empire: International Branches and Cultural Clashes
• Chapter 21 The Hard-Style Philosophy: Osu and the Spirit of Perseverance
• Chapter 22 Training Champions: Disciples, Rivalries, and Succession
• Chapter 23 Politics, Power, and Internal Fractures
• Chapter 24 The Final Kata: Mas Oyama's Declining Years
• Chapter 25 The Kyokushin Legacy: How Modern Full-Contact Karate Conquered the World

In the smoldering aftermath of the Second World War, Tokyo was an open wound. The Imperial dream had collapsed into rubble, poverty, and national humiliation, leaving behind a generation of young men adrift in moral and spiritual desolation. Among the survivors scouring the ruins was a fierce, restless Korean immigrant known to history as Masutatsu Oyama. Born Choi Yeong-eui, he was a man caught between cultures, identities, and the violent realities of a defeated nation. Yet out of this crucible of trauma, displacement, and existential desperation, Oyama did not merely survive; he conceived a revolutionary path that would fundamentally reshape the martial arts world. He dreamed of stripping away the polite, sterile conventions that had come to define modern Japanese karate and returning the discipline to what he believed was its primal, unvarnished essence: an absolute, uncompromising test of flesh, bone, and iron spirit.

By the mid-twentieth century, mainstream Japanese karate had largely retreated behind university walls and transformed into a safe, non-contact sport governed by theoretical points and pulled punches. To Oyama, this modern incarnation was an emasculated shadow of the deadly fighting traditions he had inherited from legendary masters like Gichin Funakoshi and So Nei-chu. Influenced profoundly by the bushido romanticism of Eiji Yoshikawa’s epic novel Musashi, Oyama abandoned civilization for the freezing crags of Mounts Minobu and Kiyosumi. Through grueling ascetic seclusion, shattering makiwara strikes, and relentless self-flagellation, he forged an indomitable physique and an iron will. When he emerged, he brought forth an audacious proclamation: true martial arts cannot exist without impact. Blood, bruising, and the terrifying shock of bare-knuckle collision were not barbarisms to be avoided; they were the only mirrors capable of reflecting ultimate truth.

This conviction catalyzed the birth of Kyokushin—literally the "Ultimate Truth." What began in an overgrown, gravel-strewn vacant lot behind a ballet studio in Mejiro quickly evolved into the most demanding full-contact fighting system on earth. Oyama’s disciples did not merely practice forms in synchronized lines; they engaged in full-power body blows, low shin kicks that echoed like splitting wood, and brutal stamina trials that pushed human physiology past its breaking point. To validate his creation on the international stage, Oyama embarked on cross-continental challenge tours, wrestling professional bouts across the United States and famously facing down charging bulls with his bare hands. While critics sometimes accused him of shameless showmanship, none could deny the raw, terrifying efficacy of the "Godhand." When Kyokushin fighters traveled to Bangkok in 1964 and dismantled elite Muay Thai champions in their own ring, the martial arts establishment had no choice but to reckon with Oyama’s revolution.

Yet Mas Oyama and the Birth of Kyokushin Karate is not merely an uncritical celebration of bone-crunching feats and martial folklore. Beneath the larger-than-life iconography of manga spreads, blockbuster tournaments, and cinematic mythmaking lay a complex human story marked by profound contradictions. Oyama was an outsider who achieved unprecedented cultural power in a notoriously insular Japan; a visionary leader whose international empire was constantly besieged by financial intrigue, intense rivalries, and inevitable organizational schisms. By situating his life against the broader historical canvas—from colonial Korea and the Pacific War to the economic explosion of post-war Japan and the dawn of global combat sports—this book seeks to separate the man from the myth, examining the historical conditions, cultural tensions, and personal demons that fueled his relentless ambition.

Readers of this volume will discover the direct lineage connecting Oyama’s bare-knuckle crucible to the rise of modern mixed martial arts, K-1 kickboxing, and the global full-contact landscape. Modern cage fighters, traditionalists, and cultural historians alike trace their contemporary understanding of fight conditioning and full-contact pressure testing directly back to the blood-stained tatami of the Ikebukuro Honbu. More than a technical treatise on punches and kicks, this book examines the indelible philosophy distilled into a single, ubiquitous utterance: Osu. Rooted in Oshi Shinobu—to push forward through pain and persevere under extreme duress—this ethos was forged in post-war desperation and remains a universal compass for anyone striving to master their own limitations.

To step into the world of Mas Oyama is to confront martial arts stripped of romantic illusions. It is an exploration of the physical extremity where technique ceases to be an academic debate and becomes a matter of raw survival. As you turn these pages, you will follow a solitary wanderer from the forgotten villages of Korea through the ash heaps of post-war Tokyo, up into the freezing solitude of Japan’s sacred mountains, and finally onto the roaring arena floor of the World Tournament. Here lies the definitive story of how one man’s obsessive search for absolute truth shattered tradition, redefined combat, and forever conquered the world.

The landscape of Gimje in the North Jeolla province of southwestern Korea stretches out into wide, flat alluvial plains, framed in the distance by jagged granitic hills. In 1923, the region was an agrarian world governed by the rhythm of rice harvests, monsoon cycles, and the heavy, bureaucratic apparatus of the Japanese colonial empire. It was here, in the village of Waryong, on June 4, 1923, that Choi Yeong-eui drew his first breath. Decades later, under the name Masutatsu Oyama, he would become an almost mythical icon in Japan and across the globe. But to the villagers of Waryong, he was merely the fourth son of a prominent local landholding family, born into a country that had been stripped of its sovereignty thirteen years before.

The Choi family belonged to the traditional yangban, the educated scholar-aristocratic class of old Korea. His father, Choi Min-dal, was a man of substantial standing in the local prefecture, possessing broad tracts of arable land and holding civil responsibilities under the colonial municipal administration. Min-dal was an authoritarian patriarch who maintained a traditional Confucian household: filial piety was absolute, classical Chinese texts were committed to memory by rote, and personal decorum was expected to remain flawless. The household was spacious, surrounded by tiled-roof outbuildings and earthen walls, insulated from the immediate penury that afflicted the landless Korean peasantry under the colonial rice-requisition policies of the Governor-General. Yet, prosperity in colonial Korea was always an unstable, fragile business. It required delicate compromises with Japanese authorities, an uneasy balance between preserving Korean aristocratic pride and bowing to the administrative realities of an imperial overlord.

Young Yeong-eui, however, proved from his earliest years to be a poor fit for the sedentary decorum expected of a young yangban scion. He was a broad-shouldered, barrel-chested boy, uncommonly stout, stubborn to a fault, and brimming with a physical restlessness that drove his father to distraction. While his older brothers sat obediently beneath the tutelage of private instructors, reciting the analects and practicing calligraphy with inkstone and brush, Yeong-eui looked out the paper-screen windows toward the fields. Books made his head ache, but physical contest made him feel alive. Whenever the neighborhood boys gathered on the banks of the irrigation canals, Yeong-eui inevitably found himself in the center of the dust, grappling in traditional ssireum—the ancient folk wrestling of Korea.

Ssireum was an elemental, visceral contest. Two combatants locked into a mutual grip on a fabric sash or satba tied around the waist and right thigh, digging their bare toes into the sand. The objective was simple: force any part of the opponent’s body above the knee to touch the ground through leverage, hip throws, leg sweeps, or sheer explosive lifting power. Yeong-eui possessed an exceptionally low center of gravity and thick, trunk-like legs that made him almost impossible to uproot. He reveled in the violent tug of war, discovering early on that he could absorb punishment that sent other boys limping home in tears. When he won, he celebrated with unrestrained, boisterous laughter; when he lost, he demanded an immediate rematch, nursing grievances until he could reverse the outcome.

This unruly disposition alarmed his father. Choi Min-dal envisioned his sons as modern administrators, lawyers, or professionals who could navigate the dual worlds of Korean society and the Japanese colonial bureaucracy. Yeong-eui’s growing reputation as a neighborhood terror who ruined his silk coats in rough-and-tumble street scraps ran entirely counter to the family’s aspirations. Sometime around the age of eight or nine, a family decision was made: the boy needed a drastic change of scenery. He was sent away from the family seat in Gimje across the border into southern Manchuria, to live on a farm operated by his older sister and her husband.

Manchuria in the early 1930s was a vast, lawless frontier. Following the Mukden Incident of 1931, the Imperial Japanese Army had invaded the territory, wrenching it from Chinese warlord control and establishing the puppet state of Manchukuo under the nominal reign of the last Qing emperor, Puyi. It was a territory of extremes: blistering summers that baked the loess soil into dust, winters so bitter that breath froze instantly upon the collar, and vast plains roamed by mounted bandits known as honghuzi (Red Beards), displaced peasants, Japanese soldiers, and Korean emigrants seeking land.

For an adventurous, headstrong boy, Manchuria was not an exile; it was a grand adventure. Life on the sister’s frontier estate lacked the stifling social constraints of Gimje. The chores were heavy, requiring long hours of manual labor in the open air. Yeong-eui cleared brush, carried heavy buckets of water, chopped firewood, and hauled sacks of grain. The work acted like a forge on his already robust frame. By his tenth year, his shoulders had widened significantly, and his hands had thickened from daily exposure to rough timber, stone, and heavy iron implements.

It was during this Manchurian interlude that Choi Yeong-eui had his first meaningful encounter with structured martial arts. Working on his sister’s farm was an itinerant seasonal laborer, a northern Chinese man whom Yeong-eui later referred to in his memoirs under the phonetic Japanese name "Mr. Yi" (often identified by researchers as Li). Yi was an enigmatic figure, quiet and weathered, who performed backbreaking farm work with an unusual, fluid economy of movement. The curious boy watched him closely and discovered that, in the evening hours after the sun dipped below the Manchurian horizon, the farmhand would retreat behind the granary to perform solo training routines.

These were the traditional forms of northern Chinese martial arts, likely a branch of Northern Shaolin or chazi-quan. Unlike the grounded, hip-driven grappling of Korean ssireum, Yi’s movements were kinetic, sweeping, and rhythmic. He leaped through the cold air, threw snapping kicks that whistled against the wind, and drove his palms into the trunk of a willow tree with explosive, whipping force. Yeong-eui was spellbound. He had never seen human violence codified into such an aesthetic, deadly geometry.

Day after day, the boy shadowed the laborer, begging to be taught. Yi initially ignored him, treating the landowner’s young relative with polite indifference. Traditional martial arts masters in China were notoriously reluctant to impart their family or regional systems to strangers, let alone an impetuous Korean boy who seemed eager merely to beat up other children. But Yeong-eui’s defining personality trait—an obsessive, relentless persistence that would later characterize his entire career—wore down the older man's resistance. After weeks of pestering, Yi relented on one condition: the training would not be fun, it would not be glamorous, and if the boy complained once, it would terminate immediately.

The training was grueling. Yi did not start by teaching flying kicks or secret killing strikes. Instead, he forced the boy into deep, agonizing stances. The mabu, or horse stance, was held for endless minutes while the thighs burned, the knees trembled, and sweat cut tracks through the Manchurian dust on Yeong-eui’s face. Whenever his hips rose to relieve the strain, a sharp birch switch from Yi corrected the posture. Following stance work came repetitive conditioning: striking bundles of bamboo reeds, kicking into soft earth, and running up steep dirt embankments.

Only after the boy demonstrated that he could endure physical misery without running back to his sister’s farmhouse did Yi begin to teach him actual movements. He imparted the fundamental taolu (forms) of Northern Shaolin, often referred to in Oyama’s later Japanese writings as the "Eighteen Hands of Luohan" or general Chuan Fa. These forms emphasized full extension, rapid footwork, jumping, and the integration of breath with explosive physical delivery. For the first time, Yeong-eui learned how to align the joints of his arm and wrist to deliver an impact without damaging his own structure, and how to use the rotational torque of the hips to generate power far beyond raw muscular exertion.

The training under Yi lasted roughly two years, ending when changes in family affairs required Yeong-eui to return to Korea. Though he had by no means mastered the vast, intricate catalog of northern Chinese boxing, the experience proved transformative. It gave him an unshakeable belief that physical conditioning was the absolute foundation of fighting prowess. More than that, it opened his mind to the concept that physical violence could be cultivated into an art form, a systematic science of self-perfection through pain.

Upon his return to the family home in Gimje around 1935, Yeong-eui was no longer a pudgy, misbehaved boy. He was a physically formidable adolescent, hardened by Manchurian winds and daily physical labor. His return to regular primary education in Korea, however, did not go smoothly.

Under the Japanese colonial policy of Naisen ittai ("Japan and Korea are one body"), the colonial administration had begun a concerted effort to assimilate the Korean population. Schools were compelled to conduct instruction in Japanese, children were punished for speaking their mother tongue in class, and the daily school routine was steeped in rituals of imperial allegiance, including morning bows toward the imperial palace in Tokyo and the recitation of loyalty oaths. For the proud children of former yangban families, this atmosphere was charged with suppressed resentment and cultural dislocation.

Yeong-eui possessed an inherent defiance toward authority that made compliance nearly impossible. He was proud of his Korean blood, fiercely protective of his siblings, and utterly unwilling to lower his eyes when confronted by teachers or colonial officials. Outside the classroom, he gravitated toward physical rivalries. Korean boys often clashed with the sons of Japanese colonial administrators and railway officials who lived in separate, privileged enclaves within the larger towns. In these street skirmishes, Yeong-eui’s combination of ssireum wrestling leverage and the Chinese striking techniques he had learned in Manchuria made him an unstoppable force. He was fearless, rushing headlong into brawls without the slightest hesitation, entirely indifferent to cuts, bruises, or torn clothing.

Recognizing that the local schools in Gimje could not contain their son's volcanic temper, and hoping that a disciplined academic environment might salvage his prospects, his parents enrolled him in a middle school in Seoul (then officially designated by the Japanese colonial government as Keijo). The Choi family had relatives in the city, and it was thought that the sophisticated environment of the colonial capital would curb his wild instincts and prepare him for higher education.

Instead, the move to Seoul only widened the scope of his physical exploration. Seoul in the mid-1930s was a bustling, contradictory metropolis where modern Western fashions, traditional Korean customs, and Japanese colonial institutions collided. In the alleys of the Jongno district and near the foot of Mount Namsan, various martial disciplines were quietly practiced.

While in Seoul, Yeong-eui was exposed to modern Western combat sports, most notably boxing. Modern pugilism had gained a foothold in East Asia, popularized by university clubs and visiting foreign sailors. Yeong-eui was fascinated by the rhythm, footwork, and clean, devastating efficiency of the Western jab, cross, and hook. Unlike the expansive, circular motions of Chinese Chuan Fa, boxing was compact, economical, and focused on landing concrete damage with maximum speed. He spent hours sparring with local amateur boxers, learning how to tuck his chin, roll with incoming blows, and generate torque through the balls of his feet.

At the same time, he caught glimpses of traditional indigenous Korean kicking games, most notably Taekkyeon. Though pushed underground or relegated to rural festivals by the colonial authorities, who viewed traditional martial gatherings with deep suspicion, Taekkyeon was kept alive by practitioners in the outskirts of Seoul. Its circular, rhythmic low kicks, sweeping footwork, and flowing, dance-like entries formed an intriguing contrast to both the rigid stances of Chinese boxing and the direct punches of Western pugilism. Yeong-eui was an omnivorous observer of violence; anything that worked, anything that caused pain or took a man off his feet, commanded his immediate, undivided attention.

Despite his physical pursuits, his academic life was rapidly unraveling. Yeong-eui had little patience for the classroom. He found textbooks lifeless and resented the rigid discipline of the schoolmasters, whose corporal punishment he met with cold, insolent glares. His father’s letters from Gimje became increasingly stern, demanding that he buckle down, pass his examinations, and pursue a path worthy of the family name. But Yeong-eui was dreaming a completely different dream.

By 1937, the political horizon across East Asia was darkening rapidly. The Marco Polo Bridge Incident in July of that year initiated the Second Sino-Japanese War. The Japanese empire was expanding aggressively into mainland China, and the colonial propaganda apparatus shifted into overdrive. Radio broadcasts, newspapers, and cinema newsreels were filled with stirring, dramatic reports of Imperial Japanese Army and Navy exploits.

Among these, nothing captured the imagination of East Asian youth more powerfully than aviation. The airplane was the supreme symbol of modern technological power, chivalry, and daring. Japanese combat pilots were lionized in the press as the modern incarnations of the ancient samurai—knights of the sky who dueled above the clouds. Recruitment posters appeared throughout Seoul and other Korean cities, urging young, ambitious men to volunteer for aviation preparatory academies in the Japanese home islands.

For Choi Yeong-eui, this propaganda was an intoxicating siren song. He did not care about the grand geopolitics of the Greater East Asia Co-Prosperity Sphere, nor did he possess an innate ideological loyalty to the Japanese Emperor. What he saw was an escape hatch. In Japan, he imagined, a young man could break free from the claustrophobic expectations of a provincial Confucian family, escape the dreary fate of a colonial bureaucrat, and become something heroic, modern, and formidable: a fighter pilot.

When he raised the idea with his father, the response was an absolute, furious refusal. Choi Min-dal had not spent his family wealth to have his son cross the sea and risk his life as cannon fodder for the Imperial military. He forbade the boy from even speaking of aviation, demanding that he finish his schooling in Seoul and prepare for a career in commerce or law.

The clash of wills between father and son was absolute. Yeong-eui, now nearly fifteen years old, stood almost as tall as any grown man in his village, with the heavy chest and thick forearms of an adult laborer. He had no intention of letting his life be dictated by the expectations of the Gimje estates. If his father would not give him permission and funds to pursue his ambition, he would go anyway.

In the early spring of 1938, Choi Yeong-eui packed a single bag with a few clothes and what little money he had managed to save or borrow. Without receiving his father’s blessing, and without saying a formal farewell to his mother, he left his school in Seoul and boarded a train heading south toward the port city of Busan.

As the train rattled through the Korean countryside, past the thawing paddies of his homeland, the boy stood on the platform between the cars, watching the telegraph poles whip past. Behind him lay the traditions of the Choi lineage, the rice fields of Gimje, and the childhood identity that had contained his volcanic spirit for fifteen years. Ahead of him lay the Korea Strait, and beyond that, the industrial, militarized heart of an empire preparing for total war. He had no money, no connections in the Japanese metropolis, and no clear understanding of the brutal racial hierarchies that awaited a colonial subject in the imperial capital. All he possessed was a stubborn will, an iron body conditioned by years of physical combat, and an insatiable desire to make the world bend to his presence.