Masutatsu Oyama, born Choi Yeong-eui on July 27, 1923, in Korea during the Japanese occupation, later became one of the most influential martial artists in history. Better known worldwide as Mas Oyama, he was the founder of Kyokushin Karate, a style widely recognized as one of the first major full-contact karate systems. Although Korean by birth, he spent most of his life in Japan and officially obtained Japanese citizenship in 1964. He also studied at Waseda University, where he focused on sports science.
As a child, Oyama was sent to Manchuria in northeastern China to live on his sister’s farm. It was there that he first encountered martial arts, training under a Chinese farmer who introduced him to traditional Chinese fighting methods at a very young age. Stories from his early years often describe his intense discipline and obsession with physical development. One well-known anecdote tells of his teacher giving him a seed to plant, instructing him to jump over the growing plant every day as it became taller. The story sounds almost mythical now, but it reflects the mindset that would define his entire life: relentless self-improvement through hardship and repetition. Humanity has always loved turning disciplined fighters into half-legendary mountain creatures. Apparently suffering becomes more respectable once someone breaks boards dramatically enough.
In 1938, Oyama moved to Japan following his brother, who had joined a military aviation school. During this period, he adopted the Japanese name Oyama Masutatsu. Fascinated by Japanese culture and determined to build a future for himself, he dedicated his life to martial arts training. After World War II ended, life remained difficult for him. As a Korean living in Japan, he experienced discrimination and isolation, struggling at times to find housing or acceptance.
His karate journey began with Shotokan training under the influence of the Funakoshi family, including the dojo founded by Gichin Funakoshi, one of the most important figures in modern karate history. He later studied Goju-ryu under So Nei Chu, another Korean martial artist living in Japan. Even with these prestigious teachings, Oyama constantly searched for something beyond technical mastery. He believed true strength came from pushing both the body and mind to their absolute limits.
Driven by this philosophy, he isolated himself in the mountains of Japan for long periods of harsh training. Living in solitude with minimal comfort, he followed an extreme routine of physical conditioning, meditation, and mental discipline. During these years, he was deeply influenced by The Book of Five Rings written by the legendary swordsman Miyamoto Musashi. Oyama later described the book as one of the most important influences on his life and philosophy.
In the early 1950s, he opened his own dojo in Tokyo. His approach quickly gained attention because it differed greatly from many traditional karate schools of the time. Oyama emphasized realism, endurance, and full-contact fighting. The style he developed was eventually named Kyokushin, meaning “the ultimate truth.” Training was famously intense, demanding both physical toughness and mental resilience from students.
Oyama became internationally famous through spectacular public demonstrations and extreme fighting challenges. He completed the legendary 100-man kumite, fighting one opponent after another in an exhausting endurance test. He was also known for demonstrations involving bulls, where he reportedly fought the animals bare-handed. These events helped build his near-mythical reputation, although critics later argued that the bulls were restrained and disadvantaged during the exhibitions. Martial arts history has an odd habit of mixing philosophy, suffering, and deeply questionable public relations into one package.
In 1964, Oyama officially founded the International Karate Organization Kyokushinkaikan to support the rapid expansion of Kyokushin around the world. Under his leadership, dojos opened across Japan, the United States, Europe, Australia, Brazil, and many other countries. Major tournaments were also created, including the All Japan Full Contact Karate Championships and the World Full Contact Karate Championships held in Tokyo.
Many well-known martial artists trained under him or were influenced by his methods, including Sonny Chiba, Steve Arneil, Tadashi Nakamura, and Shokei Matsui. His impact extended far beyond karate itself. Manga, films, anime, and video games drew inspiration from his life and personality. The famous manga Karate Baka Ichidai helped transform him into a cultural icon in Japan, while characters in fighting games and martial arts series were often modeled after his image and philosophy.
Even in his later years, while suffering from osteoarthritis and declining health, Oyama continued teaching and demonstrating karate. He wrote more than eighty books, several of which were translated internationally. His book What Is Karate, published in 1963, became a worldwide bestseller and remains highly respected among martial artists today.
Mas Oyama passed away from lung cancer on April 26, 1994, at the age of seventy. By the time of his death, Kyokushin had become one of the largest and most influential martial arts organizations in the world, with millions of practitioners across more than one hundred countries. Not bad for a man who once disappeared into the mountains to train alone until his eyebrows apparently became strategic psychological weapons.