Louis Diamond Phillips (né Upchurch; born February 17, 1962) is a Filipino-American actor and film director. His breakthrough came when he starred as Ritchie Valens in the biographical drama film La Bamba (1987). For the Academy Award-nominated Stand and Deliver (1988), Phillips was nominated for a Golden Globe Award and won an Independent Spirit Award. He made his Broadway debut with the 1996 revival of The King and I, earning a Tony Award nomination for his portrayal of King Mongkut of Siam. Phillips' other notable films include Young Guns (1988), Young Guns II (1990), Courage Under Fire (1996), The Big Hit (1998), Brokedown Palace (1999), Che (2008), and The 33 (2015). In the television series Longmire, he played a main character named Henry Standing Bear.
Phillips was born February 17, 1962, at the Subic Bay Naval Station in the Philippines, the son of Lucita Umayam Arañas and Gerald Amon Upchurch (1935–1963), a Marine KC-130 crew chief. His mother, a native of Candelaria, Zambales, is Filipina and his father was an American of Scots-Irish and partial Native American descent.