Isshinryu Karate had its origin from the island of Okinawa. It was founded by Tatsuo Shimabuku and was derived from several older classic styles. Master Shimabuku took the best of Shorin-ryu and Goju-ryu to improve and develop what we know today as Isshinryu. Shorin-ryu is a style known for it's graceful, quick and powerful movements that utilize hard, direct, and soft circular blocks. Goju-ryu is noted for it's dramatic breathing methods (soft but firm breathing from deep in the abdomen).
Tatsuo Shimabuku had three main teachers: from Shorin-ryu - Motubo Choki and Chotoku Kiyan and from Goju-ryu - Chogun Miyagi. From Motubo, Shimabuku learned of kumite (fighting skills) and Naihanchi kata. From Kiyan, Shimabuku learned some of the other katas in our style: Seisan, Wansu, Chinto, and Kusanku. From Miyagi, Shimabuku learned Seiunchin and Sanchin. The only kata not derived from another style is Suansu, which Shimabuku himself developed.
Shimabuku also studied Kobu-jutsu under Taira Shinken and learned weapons. Shimabuku felt a karate system without weaponry was incomplete. He felt it preserved an important part of Okinawan culture and the Samurai spirit. He also felt that the study of ancient weapons could be used in any time frame no matter how advanced our culture became.
Tatsuo Shimabuku understood that no two people were the same and would not be able to perform exactly as the instructor due to physical limitations and mental capabilities. He took his student's suggestion to name the style Isshinryu meaning "One Heart Way". "One Heart" stands for a man's character and without a good heart or character, a man had no place in his karate system. He believed that a man with a bad character or poor manners had a bad heart. A man should show respect and courtesy to everyone and not try to intimidate people with his karate skills.
Shimabuku believed that karate had four purposes:
1. To develop and strengthen the mind, body and spirit.
2. To gain self-confidence and control over one's life.
3. To gain self-discipline and self respect.
4. To gain a means of self-protection (never to be misused)
Tatsuo Shimabuku saw Isshinryu as a way to better one's life, not as an art of violence. He originally did not name his style and never wrote a book saying how Isshinryu "should be done" (as if he wanted people to venture out on their own and let curiosity be their teacher). Shimabuku passed on his knowledge only to serious students and felt that you would only get out of karate what you put in.
Don Nagle, Edward Brown, Steve Armstrong and Harold long studied directly under Tatsuo Shimabuku and have been greatly responsible for the spread of Isshinryu in the United States.