http://www.imdb.com/title/tt1905010/
 
http://en.wikipedia.org/wiki/Yamada:_The_Samurai_of_Ayothaya

Yamada: The Samurai of Ayothaya (Thai: ซามูไร อโยธยา) is a 2010 Thai action movie directed by Nopporn Watin. The film features renowned Muay Thai boxers Buakaw Por. Pramuk, Saenchai Sor. Kingstar, Yodsanklai Fairtex, and Anuwat Kaewsamrit along with the main cast of actors.
Plot

A Japanese samurai named Yamada (Ozeki) is captured by enemy Siamese warriors. To his surprise, the people whom he has been fighting and killing nurse him to health and treat him as a guest in their village. In time, his loyalty switches sides and he vows to defend the villagers who have treated him with such kindness. Turmoil results as the Japanese are intent to kill the traitor.
Historical basis

The lead character in the film is based on Yamada Nagamasa, a Japanese adventurer who later became a governor in the Ayutthaya Kingdom.