Jujutsu is one of the oldest forms of hand-to-hand combat in Japan. Records of Jujutsu date back over years. It is also the base for many other more modern martial arts, including Judo, Karate and Aikido.
"Aikido is generally believed to represent circular movements. Contrary to such belief, however, Aikido, in its true Ki form, is a fierce art piercing straight through the center of opposition." - Morihiro Saito, Traditional Aikido Volume 5. More from Saito Sensei in "Budoka no Kotae – Talking to Morihiro Saito Sensei", on the Aikido Sangenkai blog: https://www.aikidosangenkai.org/blog/budoka-no-kotae-morihiro-saito-part-1/