Mr. Ohshima is the founder and Shihan (Chief Instructor) of Shotokan Karate of America (SKA), as well as many other international Shotokan organizations, including those in Canada, France, Israel, Belgium, Curacao, Gabon, Indonesia, Morocco, Spain, and Switzerland.

Mr. Ohshima was born on August 6, 1930, and practiced Sumo, Kendo, and Judo from his elementary school days through high school. When he entered Waseda University in Tokyo in 1948, he began to study under one of the greatest Karate masters of all time, Gichin Funakoshi. In 1952, Mr. Ohshima became captain of the Waseda University Karate Club, and in 1953 he graduated from Waseda University with a BA in economics. In 1955, Mr. Ohshima left Japan to study at USC in Los Angeles, where in January 1956, he led his first U.S. practice. The first university karate club in the U.S. was founded by Mr. Ohshima at the California Institute of Technology in Pasadena, CA, in 1958. In 1969, the Shotokan Karate of America organization was formed, and the purposes and ideals which guided its members then are the same ones being pursued by today's SKA karateka.