He is the man behind a lot of dojos in the south part of Sweden. He invited Soke Richard Morris to Sweden in the late 70s and he started up 25 dojos at the time in the area.

Soke Erik Karlsson, 10th Dan became one of the finest Jiu Jitsu masters in the world under the able guidance of Japanese master Soke Inoue from Hontai Yoshin Ryu. He is now the Chief Instructor for Hontai Yoshin Ryu in Sweden. Every year he travels to the Honbu Dojo in Japan to develop his skills in the ancient Japanese arts of jujitsu and Iaido.

Soke Karlsson is the founder and Chief Instructor of the Swedish Jujitsu School. Other grades that he holds are: 9th Dan Hoku Shin Ko Ryu Jujutsu, 5th Dan Hontai Yoshin Ryu Jujutsu, 4th Dan Hontai Yoshin Ryu Iaido, 3rd Dan Toyama Ryu Iaido and 1st Dan Ninjutsu.