October 10, 1859 – April 25, 1943
Takeda Sokaku was a reknowned martial arts master of Daitō-ryū Aiki-jūjutsu and Ono-ha Itto-ryu swordsmanship. During his lifetime he is credited with teaching many famous martial artists among them the swordsman Shimoe Hidetaro, Aikido founder Ueshiba Morihei, as well as many politicians, military officers, judges, policemen, and other persons of high social standing from all over Japan.
December 14, 1883 – April 26, 1969
The founder of Aikido, Morihei Ueshiba (O Sensei), was a skilled exponent and teacher of Daitō-ryū Aiki-jūjutsu. Many of his recognised first generation Aikido students were awarded menjo certificates bearing the Daitō-ryū designation. As Ueshiba grew older, more skilled, less physically capable and more spiritual in his outlook, his teaching of his art changed, became softer and more circular, striking techniques becoming less important and the formal curriculum simpler leading eventually to the formulation of his own system, which he promoted as Aiki-Budo and Aikido.
March 15, 1900 – December 25, 1979
Kenji Tomiki was the first student to be awarded a teaching menjo (Menkyo Kaiden or license of transmission, equated later to an 8th Dan) by the founder, Morihei Ueshiba. A renkowned and active teacher of both Judo and Aikido throughout his life, Professor Tomiki formulated a new method of teaching Aikido suitable for adoption by universities as well as introducing competitive Aikido (Aikido kyogi) into regular practice. Due to this innovative approach a rift occurred with the direct decendents of O Sensei leading to his eventual departure from the Aikikai, the formation of the Japan Aikido Association and founding of the Shodokan Dojo where he continued his research. Aikido taught using the teaching and practice methods of Kenji Tomiki is often referred to as Shodokan Aikido, Tomiki Aikido and/or Sport Aikido.
Read more about Kenji Tomiki and Shodokan Aikido here