Aikido is a martial art founded by Morihei Ueshiba in Japan, based on the concept of "aiki" as originally taught in its predecessor art, Daito-Ryu Aiki-Jujutsu, which was founded by Takeda Sokaku. Morihei Ueshiba was a famous peer of Jigoro Kano, and due to their interactions, had some input on Kodokan Judo and thus even Brazilian Jiu-Jitsu.