Judo made its first appearance in the 1964 games, which were hosted in Tokyo, Japan. This Olympics was the first held by a non-Western nation and also introduced volleyball to the Olympics. Japan had originally won the right to host the 1940 Olympics. However, because of their invasion of China the honor was passed onto another country and subsequently the Olympics were cancelled due to World War II. The delay could not have been better for Judo as the international recognition of Judo did not start developing until a decade later with the first World Championships in 1956.

For the 1972 games, Judo was selected to become a full medal sport. During these early games, in addition to three basic weight classes (heavy, middle, and light) Judo also had an “open” format, which allowed any weight-class to compete against one another. In theory, this echoed back to the truest form of Judo, where weight and stature should not affect a Judo artist’s ability. However, over time it became recognized that when skills are truly equal, the weight and stature of the artists does affect the outcome. Thus in 1988, the “open” format was dropped.

Over time and as interest in the sport grew, more divisions were created to account for different breakdowns in weight. In 1992, women were finally allowed to compete in Judo as well. The International Judo Federation, which is one of if not the largest Judo organization in the world, is part of the International Olympic Committee and helps to set the guidelines competitors follow.

The participants who practice Judo are referred to as “Judoka”, the proper name of those that practice Judo. Nearly 45 nations have won medals in various Olympics, the highest being Japan with 58 medals prior to the 2008 Olympics. Each weight class has four medals given: Gold, Silver, and two Bronze. The Gold and Silver are awarded based on the winner and other competitor in single elimination brackets. The Bronze medals are determined from the two other semifinalists facing a repachage of those defeated by the top seats.

In 1964, the Gold medalists were:
- Takehide Nakatani (Japan) – Lightweight
- Isao Okano (Japan) – Middleweight
- Isao Inokuma (Japan) – Heavyweight
- Anton Geesink (Netherlands) -- Open