Charles H. Mason (1830 – July 29, 1859[1]) was an American politician, the first Secretary of State for Washington Territory, and acting Governor[2] for two and a half years while the territorial Governor, Isaac Ingalls Stevens, conducted railroad surveys and concluded treaties with First Nations tribes and confederations.

[4] As Acting Governor he served the state in time of war, from October 1855 to January 1856, as hostilities between settlers and First Nations peoples erupted in Snohomish, King, Pierce, and Thurston counties.

Mason called for volunteers, maintained peaceful relations with non-hostile bands, and treated all parties with fairness.

[5] In all he served four stints as acting Governor:[1] Mason died after a brief illness at Olympia, Washington Territory.

[3] His burial location was established by the Washington state Archivist from the primary source material and his grave marked in 1997 following an extensive search.