Although Taekwondo first appeared in the Koguryo kingdom, it is the Silla's Hwarang warriors that are credited with the growth and spread of Taekwondo throughout Korea. Silla was the smallest of the three kingdoms and was always under attack by Japanese pirates. Silla got help from King Gwanggaeto and his soldiers from the Koguryo kingdom to drive out the pirates. During this time a few select Sillan warriors were given training in Taek Kyon by the early masters from Koguryo.
The Taek Kyon trained warriors 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 guiding principles of the Hwarang warriors were loyalty, filial duty, trustworthiness, valor, and justice. The makeup of the Hwarang-do education was based on the Five Codes of Human Conduct written by a Buddhist scholar, fundamental education, Taek Kyon and social skills. Taek Kyon was spread throughout Korea because the Hwarang traveled all around the peninsula to learn about the other regions and people.