Ancient history of judo

Teaching Principles
Kano used four main teaching methods in his dojo: “Katas” (prearranged forms), “Randori” (free practice), “Mondo” (question and answer sessions), and “Ko” (systematic lectures). This leads to philosophical debates between Kano and his students, which lead to Judo’s second principle: “Jita-kyoei” (mutual benefit and prosperity). 
Kano believed learning Judo would make students realise they could not progress at the expense of others and that mutual prosperity is the key to real, lasting progress. Kano’s belief in this principle was so strong that he made growing the sport of Judo his top priority in life so students could eventually figure out the second principle on their own. 
Kano traveled to the Americas and Europe in 1899 to promote Judo, and he traveled to Cairo, Egypt in 1938 to attend the International Olympic Council meeting where he managed to get Tokyo nominated for the 1940 Olympics. He passed away on a ship back to Japan after the conference at age 78. 
The technical aspects of Judo reached full maturity in the 20^th century when 18 leaders of the leading Jiu-Jitsu ryus joined Kano’s system. Judo continued to be refined until it was officially added to the Olympic games in 1964 and has remained a part of the event ever since. 

Judo's Beginning

The form of Judo currently being practiced in Japan and around the world was first introduced in 1882 by Jigoro Kano, who began Judo instruction on the grounds of the Eishoji Temple in Tokyo's Kita inari-cho district (currently the Higashi Ueno area of Taito-ku, Tokyo).
Jigoro Kano began by studying the various forms of Jujutsu, Japan's ancient combative art, and then introduced his own wide-ranging improvements, as well as new techniques and a teaching system. Jigoro called his system "Judo", based on the concept that Judo provides "the way" (spiritual) which in turn leads to "technique" (physical).

The spread of Judo

As the number of Judo practitioners increased and the organization grew in size, a number of official events began to appear. Around 1887, some schools began offering Judo as an after-school program, and in 1931 it was offered as part of the regular curriculum. Judo training was also adopted by police departments, as well as by the military, private companies, and local sports training halls.
Interschool Judo competitions became popular, and these evolved to become all-Japan competitions.