According to legend, the Buddhist monk Bodhidharma, founder of Zen Buddhism, arrived from India at the Shaolin temple of China in 527. He found the monks in inadequate shape for Zen meditation (Chan, in Chinese), therefore he taught them some body practices and combat techniques that, blended with Chan (Zen) philosophy, gave life to the Shaolin style of Kung Fu (Hard Work, in Chinese). The high spiritual charge and the care for the body-mind system created the foundations of martial arts (Wu Shu, in Chinese) as both self-defense techniques and meditation in motion.
Like many traditions, even the philosophy of martial arts arrived in Japan from China through Korea. Chan Buddhism became Zen and martial arts became Bujutsu. Through centuries, Japanese warriors, or Bushi, developed fine combat techniques both armed and unarmed. With time, a highly influencial warrior class arose, which rapidly took control of the country: the Samurai.
The strict samurai code of conduct is today called Bushido, the Way of the Warrior. For example, egoism is a capital flaw to a samurai. It has to be eliminated starting from any everyday life’s trivial occasion. At a banquet, a samurai will have to see to it that all the others get the biggest portions. For a samurai, the boundary between right and wrong is feeble: to destroy someone else’s life, believing we’re on the right side would put us immediately on the wrong side. Furthermore, a samurai will never engage in verbal disputes, knowing them to be irrelevant.
The Samurai’s elite weapon was the Katana, a razor-sharp, very finely manufactured sword that led them to develop highly refined and lethal combat techniques known as Ken Jutsu. The Samurai also practiced wrestling combat (Ju Jutsu) and various types of armed combat. All those techniques are called Bu Jutsu in Japanese and are all focused to war combat.
By the early 1600s, Japan was united under the Tokugawa shogunate and civil wars were practically over. From then on, the Samurai had fewer and fewer chances for combat. In order to preserve their warrior knowledge, they created several schools (Ryu) of Bu Jutsu, so they could continuously practice their techniques and keep trained. With time, Bu Jutsu started to mingle with Bushido, the warrior’s code, and Bu Do was developed. Budo, the Martial Way (Way to Stop the Conflict, literally), is a practice to strengthen body, mind, and soul through the study of weapons and combat.
In western countries the words Bujutsu and Budo have both been translated as Martial Arts, generating a certain confusion between something merely concerning combat (Bujutsu) and something else that is focused on self-improvement (Budo). Aikido is a form of modern Budo born in the 40s from the synthesis that the founder Morihei Ueshiba achieved thanks to his enormous knowledge of Bujutsu, especially of Daito-Ryu Aiki Jutsu and Kashima Ryu Ken Jutsu.