Kano founds judo

In 1882 Kano Jigoro, a 22-year-old graduate of Tokyo Imperial University, opened a small training hall called the Kodokan at the Eishoji temple in Tokyo with a handful of students. He called his new art judo, meaning 'the gentle way'. It was built from the throws, pins and joint locks of older jujutsu schools, which Kano had studied as a student, but he removed the most dangerous techniques and added a safe way to practice them at full effort.¹²

Japan in the 1870s was in the middle of the Meiji Restoration, and the samurai class that had kept jujutsu alive had lost its privileges and its swords. Many teachers were poor and their schools were fading. Kano, who was small and wanted to learn how a weaker person could beat a stronger one, collected the best methods from several schools and reorganized them around two principles: using the least effort for the greatest effect, and mutual welfare between partners. He introduced free sparring called randori, a graded system of ranks (dan and kyu) that later became the colored belts, and he presented judo as education for body and character, not only for fighting. His school's students proved themselves against rival jujutsu schools in public contests in the 1880s, and judo entered Japanese school curricula in the early twentieth century.²