The art was officially registered as Aikido in 1942, and the Kobukai was renamed as Aikikai in 1948. By this time, Ueshiba had removed the most dangerous techniques of Daitoryu and incorporated more circular and softer techniques much adopted from Judo. This was to gain aikido more popularity, but also due to his religious beliefs of the Omoto sect, which formed the basis for the ethical framework of aikido.
Ueshiba retired to Iwama in 1942, where he had such students as Morihiro Saito. The dissemination and technical development of aikido at the Aikikai Hombu Dojo was left to Kisshomaru Ueshiba and Koichi Tohei.
Aikido was founded by Morihei Ueshiba (1883-1969) mainly on the technical basis of Daitoryu aiki-jujutsu. Sokaku Takeda (1859-1943), who is said to be the reviver of Daitoryu, granted Ueshiba with Kyoju Dairi teaching certification and Shinkage-ryu kenjutsu transmission scroll in 1922. > Ueshiba
Ueshiba was teaching at the Asahi newspaper dojo in 1934-1936, followed by Takeda in 1936-1939. During this time 547 techniques were secretly photographed. A few years later their student Takuma Hisa (1895-1980) organized the material into nine volumes called the Soden (1942-1944). The first six volumes contain techniques taught by Ueshiba and five of them appear under the name Aikido.
At the early age Koichi Tohei (1920-2011) studied judo, zen meditation and misogi. After a personal demonstration from Morihei Ueshiba in 1940 he started practicing aikido in order to combine bodily training with training the mind, which he felt was lacking in judo. While practicing aikido with Ueshiba, Tohei was also training Shinshin Toitsu Do ("way of mind and body unification") with Tempu Nakamura. From there he adopted e.g. the key concept "the mind moves the body".
Tohei was much responsible of spreading aikido outside Japan since 1953. He was also the only student of Morihei Ueshiba to be officially awarded 10th dan. Tohei remained as the chief instructor of the Aikikai Hombu Dojo until his departure in 1974. By this time, he had founded the organisation Ki no Kenkyukai, which now became the headquarters of Shinshin Toitsu Aikido ("Aikido with Mind and Body Coordinated"), better known as Ki-Aikido.
Rainer Varis (b. 1955) started practicing aikido and iaido in 1971 with Toshikazu Ichimura, who back then was the teacher responsible for aikido in Sweden, Denmark and Finland. In 1974 Varis was the first aikido black belt in Finland, and served as the Finnish head teacher of Finland Aikikai until leaving the organisation in 1977. After that he went to Koichi Tohei's seminars in Brussels and started studying ki-aikido with Degueldre and Yoshigasaki. Varis founded the Finnish Ki-Aikido Society in 1979 and the Finnish Ki Federation in 1993.
Kenjiro Yoshigasaki (1951-2021) started to practice yoga at the age of 10 and Aikido in 1968 as a direct student of Tohei. He came to Europe in 1977 as a regional chief instructor of the Ki no Kenkyukai. In 2001 Yoshigasaki founded his own organisation, Ki no Kenkyukai Internationale, to further develop Tohei's teachings.
The KnK Musubi network was found after Yoshigasaki's passing. It currently lists 190 dojos in 25 different countries. The contact person is Michael Holm from Denmark, who regularly visits nordic countries to do seminars.
Esa Lilja (b. 1973) started to practice judo with Timo and Matti Hautoniemi in Jushinkan Ähtäri, Finland in 1985, soon followed with karate, ryukyu kobujutsu and aikido. In the 1990s he moved to Helsinki and started studying ki-aikido with Rainer Varis, taiji, again with Timo Hautoniemi, and kendo. In 2003 he founded Ki-Aikido Shizentai Dojo in Helsinki, and also started studying Amatsu style Daitoryu aiki-jujutsu. Lilja moved to Stavanger, Norway, in 2019 and founded Ki-Aikido Karasukai in 2021.
Ki-Aikido Karasukai is connected to the Varis style of ki-aikido and the Finnish Ki Federation, and works closely together with the Ki No Kenkyukai Musubi.
During the 1930s, Ueshiba gradually separated himself from Sokaku Takeda. In 1931 he established the Kobukan Dojo in Tokyo, and the associated Kobukai (皇武会, "divine martial society").
Ueshiba began calling his art Aiki-Budo, sometimes more specifically Tenshin-ryu Aiki-budo ("tenshin" 天眞 translates to "heavenly truth").
Before the World War II, Ueshiba had such students as Kenji Tomiki (Tomiki-Aikido), Gozo Shioda (Yoshinkan Aikido) and Koichi Tohei (Ki-Aikido).