Varying battlefield situations and the technical requirements of feudal war-fare led to the establishment of various ryu (systems and styles) which were controlled by, and passed down through, the large powerful families. One of these systems was aikijujutsu. It is not completely clear where Aiki techniques were developed, but it is said to have originated with Prince Teijun, the 6th son of the Emperor Seiwa (850 - 880), and was passed on to succeeding generations of the Minamoto family. By the time the art reached Shinra Saburo Yoshimitsu, the younger brother of Yoshiie Minamoto, it seems that the foundations of modern Aikido had already been laid out. Yoshimitsu was a man of ex-ceptional learning and skill, and it is said that he devised much of his tech-nique by watching a spider skillfully trap a large insect in its fragile web. His house, Daito mansion, gave its name to his style of aikijujutsu called Daito Ryu Aikijujutsu. Yoshimitsu’s second son lived in Takeda, in the province of Kai, and his family be-came known by the name Takeda. Subsequently, the techniques of Daito Ryu were passed on to successive generations as secret techniques of the Takeda house and were made known only to family members and retainers. When Kunitsugu Takeda moved to Aizu in 1574, the techniques came to be known as Aizutodome (secret techniques). During the 16th century, Japan was embroiled in civil wars. Each feudal lord (daimyo) struggled to maintain a powerful, independent position within the country. In order to do so, each daimyo had to create a stable, unified force of his own. This required a very strong bond between the lord and his bushi. Bushido, the code of the Samurai, encouraged the development of combat techniques, cultivated the qualities of justice, benevolence, politeness, honor, and above all inculcated the idea of supreme loyalty. It was during this period of independence and feudal isolation that combat forms developed into very numerous ryu.
The next two and a half centuries (Tokugawa period) were relatively peaceful for Japan. The Samurai, as a class, saw little combat. Never the less, they continued to practice and refine the various martial arts of kenjutsu, iaijutsu, bajutsu, and forms of jujutsu. Ju is a Chinese word meaning pliable, harmonious, adaptable, or yielding; jutsu means technique. As a collective term applied to all fighting forms, the term “jujutsu” came into existence long after the forms it describes originated. Jujitsu's golden age ex-tended from the late 17th century to the mid-19th century. As the martial arts (and all of Japanese culture) became strongly influenced by Buddhist concepts, the fighting arts were transformed from combat techniques (Bugei) into “ways” (Budo), Inculcating self-discipline, self-perfection, and philosophy. The dimensions of the martial arts expanded beyond the simple objective of killing an enemy to include many aspects of everyday living. Particularly after the decline of the Samurai class, the martial “techniques” became martial “ways” and great emphasis was placed upon the study of Budo as a means of generating the moral strength necessary to build a strong and vital society. At the time, Aikido was known by many names, and remained an exclusively Samurai practice handed down within the Takeda family until Japan emerged from isolation in the Meiji period. The Meiji Revolution (1868) brought not only the return of Imperial supremacy, but also a westernized cultural, political and economic way of life to Japan. The Bushi, as a class, virtually disappeared under a new constitution that proclaimed all classes equal, but the essence of Bushido, cultivated for many centuries, continued to play an important part in the daily lives of the Japanese. Budo, being less combative and more concerned with spiritual discipline by which one elevates oneself mentally and physically, were more attractive to the common people and were readily taken up by all classes, and people of every social strata. Accordingly, kenjutsu became kendo, iaijutsu became iaido, jojutsu became jodo and jujutsu became judo.