In 1883, Kanō Jigorō, the founder of Judo, established the system of Dan ranking to measure the Judo practitioners' ability.[1] This system was referred to the Dan ranking system of Go, the ancient board game. Some organizations of academic tests started using the Kyū ranking system to measure candidates' ability.[2]
Similarly, the Tokyo Metropolitan Police Department started a ranking system using Kyū to measure the police officers' ability in Kendo. Grades were from 8th to 1st.[3]
In the 1890s, the Greater Japan Martial Virtue Society introduced the dan and kyū ranking system to other martial arts in Japan.[4]