Muay Thai evolved from the older muay boran (ancient boxing), an unarmed combat method which would have been used by Siamese soldiers after losing their weapons in battle. Some believe that the ancient Siamese military created muay boran from the weapon-based art, krabi krabong but others contend that both systems were developed at the same time. Krabi krabong nevertheless was an important influence on muay Thai as seen in the movements in the wai khru.
Muay boran, and therefore muay Thai, was originally called by more generic names such as pahuyuth (from the Sanskrit bahu-yuddha meaning unarmed combat), dhoi muay (boxing or pugilism, a cognate of the Malay word tomoi) or simply muay. As well as being a practical fighting technique for use in actual warfare, muay became a sport in which the opponents fought in front of spectators who went to watch for entertainment. These muay contests gradually became an integral part of local festivals and celebrations, especially those held at temples. Eventually, the previously bare-fisted fighters started wearing lengths of hemp rope around their hands and forearms. This type of match was called muay khat chueak (มวยคาดเชือก).