An article in the Deadwood Pioneer Times dated July 6, 1953, explains the naming of Flag Mountain. The article reads, "Probably the only place in the Black Hills where a flag has flown for 75 years on Independence Day is Flag Mountain a 6900 foot peak west of Deerfield. On July 4, 1876, Joe Reynolds a former scout for General Custer placed a flag on the peak as a warning to the surrounding settlers of a threatened Sioux uprising. On each succeeding Fourth of July until his death, he placed a flag on the original site. The custom was carried on by his sons until 1941 when a forest fire lookout was completed. Now the flag flies everyday including July 4 during the fire season."