This martial art was derived and developed from the art practiced in Shanghai China. There is a legend in Tsuken Island that in the Ryukyu Kingdom era, a samurai (warrior) called Chikin Uekata Masanori was defeated in contention for the throne. He was to be executed by being sunk in the sea. However, since he was a Bo expert, the executor couldn't bring himself to carry out the sentence. So he asked a fisherman named Asato to take care of this samurai in secret. Asato learned Bo techniques from Uekata but soon surpassed him and became a Bo expert. Asato was called "Chikin Akachu" because he had a red sun burnt face.
The Eku -also known as Kai or Ieku- is a common short oar, used similarly to the Bo. Since Kobudo utilized many farming implements, the Eku became -and still is- a very popular weapon. The Eku is made of wood. It is shorter than the Bo, usually in proportion to the trainee’s own height. It has four faces: the Saki, two Yoko sides, a side edge and a circular face. The Eku is a solely Okinawan weapon. It was used at first as an oar, until Okinawan fishermen started using it as a lethal weapon.
Eku techniques are the same as those of the Bo –but it takes a lot more skill, so that the wrist can turn to use the correct part of the weapon. Using the Eku requires excellent knowledge of the Bo techniques. Eku grips are also similar to those of the Bo. The right hand holds the weapon at Moto –right behind the Monouchi. The left hand is about a shoulder’s length behind. Similarly to the Bo, it is the right hand that gives power to the strike, while the left hand leads and controls.
Ueku is an oar for a boat. Fishermen created techniques to defend themselves from the attacker who had swords, spears, or Bo. The blade becomes a tremendously powerful weapon. This is a weapon well suited for "me-tsubushi" (to blind) kicking up beach sand. Ueku is a sword to fishermen.