Yao people, from whom Iu Mien Americans descend, arrived in Laos from Southern China during the late 1600s to 1800s. Reasons for this migration remain controversial, varying from political to socio-economic ventures. Many Iu Mien American elders involved with the United States CIA during the "Secret War" of Laos in an effort to block weapon as known Ho-Chin Min trails from the North Vietnam to the South Vietnam.