what county is mcarthur ca
McArthur, California. For the community in Modoc County, see McArthur, Modoc County, California. McArthur is a census-designated place (CDP) in Shasta County, California, United States. The population was 338 at the 2010 census, down from 365 at the 2000 census. McArthur is a small ranching community, located 4 mi east of Fall River Mills.