Sosai Masoyama ( the founder of Kyokushin karate ), was born in southern Korea in 1923. At the age of 9 he started studying southern Chinese form of kempo known as "Eighteen Hands".  When Mas Oyama returned to Korea at the age of 12, he continued training in Korean kempo.

          At the age of 15 he continued his martial arts training in judo and Boxing. Shortly afterwards, he began training at the dojo of Gichin Funakoshi, who brought karate to
Japan from Okinawa and developed what is now called shotokan. Mas Oyama progressed really fast and he was a Nidan (2nd Dan) at the age of 17 and by 20 he was a Yondan (4th Dan) in the art of shotokan.  He then focused on judo and in less than four years he became Yondan in judo.

      After World War II, Mas Oyama started training under Nei-Chi So, one of the highest authorities in Goji Ryu. Master So encouraged Mas Oyama to dedicate his life to Budo, the martial way. He suggested that Mas Oyama retreat from civilization for three years to train his mind and body without the distractions of outside world.

     Mas Oyama went to Mt. Minibus in Chiba Prefecture, where a famous samurai warrior Musashi had developed his style of sword fighting and begin his rigorous training. Along with Mas Oyama accompanied one of his students , after 6 months of training, his student was unable to handle the solitude and secretly fled during the night leaving Mas Oyama completely alone to continue his training. After 14 months of training in wilderness Mas oyamas friend told him he can no longer provide supplies of food and Mas Oyama had to return to civilization .

    Mas Oyama returned to training in wilderness after few months , this time he went to Mt. Kiyozumi, also in Chiba prefecture, which he chose for its spiritually uplifting environment. This time his training was fanatical - 12 hours a day, every day with rest days, standing under cold buffeting waterfalls, breaking river stones with hands, using trees as Makiwara, jumping over rapidly growing flax plants hundreds of times each day. After 18 months of rigorous training, Mas Oyama returned to civilization fully confident in himself and able to take control of his life.

     In 1950's he started demonstrating his power and skill by fighting bulls. In all he fought 52 bulls. He killed 3 bulls instantly and 49 of whose horns he took off with shuto. In 1952 he travelled to United States and demonstrated his karate skills on national television , during subsequent years he took many challengers and in most fights he finished them with just one technique . He would call it 'one strike, certain death' a fighting technique based on samurai warrior's principle of "Ichi Geki Hissatsu". Because of his strength and skill he became known as " the Godhand".

     In order to test his own abilities Mas Oyama decided to perform 300 men kumite in three days. He chose the strongest students in his dojo to fight him one at a time. After each had a turn they started from the beginning again until all three hundred fights were completed. Legend has it that Mas Oyama wanted to go for the fourth day and no one was willing or able to fight him .

      Since its inception Kyokushin has spread to more than 120 countries and more than 12 million practitioners, making it one of the largest martial arts styles in the world.
In 1992 Mas Oyama visited United States and was guest  of honor at 1st annual American international karate  championships in Rochester. Sadly Mas Oyama died of lung cancer in 1994. Sadly his unexpected death led to a state of confusion in his organization. International kyokushin organization then splintered into many different groups . One group of Kyokushin karateka decided to affiliate themselves with Hanshi Steve Arneil of Great  Britain  who left japanese Kyoksuhin organization in 1991 to form the international federation of Kyokushin karate IFK.