The founder of Aikido is Morihei Ueshiba, often referred to as O-Sensei by Aikido practitioners. Morihei Ueshiba developed Aikido in the early 20th century, blending his martial arts knowledge with his spiritual and philosophical beliefs. Aikido is a Japanese martial art that emphasizes harmony, non-violence, and redirecting an opponent's energy, rather than meeting force with force. O-Sensei's teachings and philosophy continue to influence Aikido practice worldwide.