What modern Japanese martial art was developed by Morihei Ueshiba, often referred to as"the founder" "Kaiso" or "Ōsensei"?
Morihei Ueshiba: Morihei Ueshiba (植芝 盛平 , Ueshiba Morihei , December 14, 1883 – April 26, 1969) was a martial artist and founder of the Japanese martial art of Aikido. Morihei Ueshiba:  He is often referred to as "the founder" "Kaiso" (開祖 ) or "Ōsensei" (大先生/翁先生 ) , "Great Teacher".
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