Jiu-jitsu is a predominantly unarmed method of combat that was developed by the Japanese samurai during the 16th and 17th centuries. On the battlefield, the samurai typically relied on their sword. When a samurai had lost his weapon he relied on his jiu-jitsu training. Developed for use on the battlefield where the samurai wore armor, jiu-jitsu originally utilized mostly grappling techniques and the use of small weapons. Striking techniques, which were ineffective against armor, were not a significant part of jiu-jitsu training until battlefield combat became more uncommon during the Tokugawa period of Japan.
Koseido-ryu Jiu-jitsu was founded by an American named Dewey Deavers in the early 20th century. Deavers was born in 1890 into a family of circus performers. In 1910, Deavers met a team of Japanese men who were traveling with the circus he was in, putting on demonstrations of jiu-jitsu. He was fascinated with jiu-jitsu and asked the team if they would teach him. Although he was repeatedly rebuffed, he kept asking and watched all of their training sessions until they finally accepted him as a student in exchange for performing chores for the group. His training consisted of a wide variety of striking techniques, throws, takedowns, joint-locking techniques, chokes, and strangles. He also learned pressure points, defenses against a variety of weapons (knife, gun, club, sword, and bayonet), and knife fighting. He learned how to set broken bones and dislocated joints, in addition to resuscitation techniques. He trained for several hours each day and eventually became a part of the demonstration team. Deavers stayed with the group until they disbanded during World War I.
Unfortunately, not much is known about Deaver's instructors or the name of the style of jiu-jitsu they taught him. Deavers said very little about who his instructors were, and most of his own students were more interested in learning jiu-jitsu techniques than inquiring about Deaver's instructors. Whenever Joseph Hedderman, the current head instructor of Koseido-ryu Jiu-Jitsu, asked Deavers about his instructors, Deavers would provide little information beyond stating that they "trained hard, were well-disciplined, and loyal to each other."
Deavers did not give a name to the style of jiu-jitsu he taught until the 1960s. Prior to the 1960s, Deavers only referred to the martial art he taught as "jiu-jitsu" or "American jiu-jitsu." In the early 1960s as martial arts became more wide spread in the United States, Deavers formally named his style of jiu-jitsu. Although Deaver's style of jiu-jitsu and training methods had always placed the goal of self defense above using training as a method of character development, he choose the name Koseido-ryu, which loosely translates to "Way of Individual Character Style."
The current head instructor of Koseido-ryu Jiu-jitsu is Joseph Hedderman who began his jiu-jitsu training under Dewey Deavers in 1950 at the age of fifteen. He trained under Deavers until Deaver's death in 1973.