Khao Kho was established as a minor district (
king amphoe) on 21 August 1984 by splitting the two
tambons Thung Samo and Khaem Son from
Lom Sak district. It was upgraded to a full district on 19 July 1991. Between 1965 and 1984, this mountainous area was a battleground in the fight between the
Thai communist party and the Royal Thai Army. ==Geography==