The Klang War or Selangor Civil War was a series of conflicts that lasted from 1867 to 1874 in the Malay state of Selangor. It was initially fought between Raja Abdullah bin Raja Jaafar, the administrator of Klang, and Raja Mahadi bin Raja Sulaiman. It was joined by Tengku Kudin (Tengku Dhiauddin, also spelt Ziauddin), as well as Chinese rival gangs. The war was eventually won by Tengku Kudin and Abdullah's son, Raja Ismail.