The oldest Korean martial art was an amalgamation of unarmed combat styles developed by the three rival Korean Kingdoms of Goguryeo, Silla, and Baekje, where young men were trained in unarmed combat techniques to develop strength, speed, and survival skills. The most popular of these techniques was subak, with taekkyeon being the most popular of the segments of subak. Those who demonstrated strong natural aptitude were selected as trainees in the new special warrior corps, called the Hwarang. It was believed that young men with a talent for the liberal arts may have the grace to become competent warriors. These warriors were instructed in academics as well as martial arts, learning philosophy, history, a code of ethics, and equestrian sports. Their military training included an extensive weapons program involving swordsmanship and archery, both on horseback and on foot, as well as lessons in military tactics and unarmed combat using subak. Although subak was a leg-oriented art in Goguryeo, Silla's influence added hand techniques to the practice of subak.
During this time a few select Silla warriors were given training in taekkyeon by the early masters from Koguryo. These warriors then became known as the Hwarang. The Hwarang set up a military academy for the sons of royalty in Silla called Hwarang-do, which means "the way of flowering manhood." The Hwarang studied taekkyeon, history, Confucian philosophy, ethics, Buddhist morality, social skills and military tactics. The guiding principles of the Hwarang warriors were based on Won Gwang's five codes of human conduct and included loyalty, filial duty, trustworthiness, valor and justice. Taekkyeon was spread throughout Korea because the Hwarang traveled all around the peninsula to learn about the other regions and people.
In spite of Korea's rich history of ancient and traditional martial arts, Korean martial arts faded into obscurity during the Joseon Dynasty. Korean society became highly centralized under Korean Confucianism and martial arts were poorly regarded in a society whose ideals were epitomized by its scholar-kings. Formal practices of traditional martial arts such as subak and taekkyeon were reserved for sanctioned military uses. Civilian folk practice of taekkyeon persisted into the 19th century.
During the Japanese occupation of Korea (1910–1945), all facets of ethnic Korean identity were banned or suppressed. Traditional Korean martial arts such as taekkyeon or subak were banned during this time. During the occupation, Koreans who were able to study and receive rankings in Japan were exposed to Japanese martial arts. Others were exposed to martial arts in China and Manchuria.
When the occupation ended in 1945, Korean martial arts schools (kwans) began to open in Korea under various influences. There are differing views on the origins of the arts taught in these schools. Some believe that they taught martial arts that were based primarily upon the traditional Korean martial arts taekkyon and subak, or that taekwondo was derived from native Korean martial arts with influences from neighboring countries. Still others believe that these schools taught arts that were almost entirely based upon karate.
In 1952, at the height of the Korean War, there was a martial arts exhibition in which the kwans displayed their skills. In one demonstration, Nam Tae Hi smashed 13 roof tiles with a punch. Following this demonstration, South Korean President Syngman Rhee instructed Choi Hong Hi to introduce the martial arts to the Korean army. By the mid-1950s, nine kwans had emerged. Syngman Rhee ordered that the various schools unify under a single system. The name "taekwondo" was submitted by either Choi Hong Hi (of the Oh Do Kwan) or Song Duk Son (of the Chung Do Kwan), and was accepted on April 11, 1955. As it stands today, the nine kwans are the founders of taekwondo, though not all the kwans used the name. The Korea Taekwondo Association (KTA) was formed in 1959/1961 to facilitate the unification.
In the early 1960s, Taekwondo made its début worldwide with assignment of the original masters of taekwondo to various countries. Standardization efforts in South Korea stalled, as the kwans continued to teach differing styles. Another request from the Korean government for unification resulted in the formation of the Korea Tae Soo Do Association, which changed its name back to the Korea Taekwondo Association in 1965 following a change of leadership. The International Taekwon-Do Federation was founded in 1966, followed by World Taekwondo Federation in 1973.
Since 2000, Taekwondo has been one of only two Asian martial arts (the other being judo) that are included in the Olympic Games; it became a demonstration event starting with the 1988 games in Seoul, and became an official medal event starting with the 2000 games in Sydney. In 2010, Taekwondo was accepted as a Commonwealth Games sport.
One source has estimated that as of 2009, Taekwondo was practiced in 123 countries, with over 30 million practitioners and 3 million individuals with black belts throughout the world. The South Korean government in the same year published an estimate of 70 million practitioners in 190 countries.