Thai Massage is the result of a blending of cultures and healing practices over hundreds, perhaps thousands of years. Thai yoga therapy is just one aspect of the Thai Traditional Medicine and is used in daily practice as a healing method.
It is commonly understood that the "father of Thai Medicine" is Shivago Komarpaj.
He was considered to be the Buddha's personal physician and came with him when the Buddha traveled throughout southeast asia, roughly 2500 years ago.
The Thai people had their local medicine, as well as were influenced by Traditional Chinese Medicine (TCM). When Shivago brought Ayurveda with him, including the practice of Yoga, the Thai people adopted these principles and blended them with their current practices to create what we know now as Thai Massage.
Although there is great influence from the local customary medicines as well as TCM, Thai Massage is more closely related to Ayurvedic medicine than TCM.
Currently in Thailand the practice of Thai massage is constantly growing and evolving. Each region has its own specific style and focus.