Charles Augustus Ropes Dimon (April 27, 1841 – May 5, 1902) was a volunteer soldier in the Union Army during the American Civil War.

The regiment left Massachusetts on January 2, 1862, arrived off the Louisiana coast in mid February, and played a minor role in the Siege of New Orleans in April and May 1862.

On August 5, 1862, Dimon and the 30th Massachusetts saw their first heavy combat during the Battle of Baton Rouge as the Confederates unsuccessfully attempted to recapture the state capital.

[10] After his recovery, in early 1864, Dimon sought a position on the staff of Maj. Gen. Butler, who was then in command of the Department of Virginia and North Carolina with headquarters at Fortress Monroe.

The regiment, organized at the prisoner-of-war camp at Point Lookout, Maryland, would consist entirely of "Galvanized Yankees", Confederate prisoners willing to take an oath of loyalty to and fight for the Union in exchange for their freedom.

However, Lt. Gen. Ulysses S. Grant, then in command of the Union army, decided that prisoner-of-war units should not be employed against their former comrades writing, "it is not right to expose them where, to be taken prisoners, they might surely suffer as deserters.

After travel by rail from New York and steamship up the Missouri River, the regiment marched the final 250 miles, reaching Fort Rice on October 17, 1864.

As commander of the post, Dimon was instructed to complete the construction of the fort, aid settlers, and manage relations with Native Americans in the region.

These included the Yanktonai and Lakota people who perceived Fort Rice as a dangerous encroachment on their homeland and led repeated raids against it.

The positive relations were fleeting, however, as the arrival of additional troops in Dakota triggered a large attack on Fort Rice by the Sioux on July 28, 1865.

Volunteers were successful in driving off the attack and the garrison survived that summer, according to historian Michele Butts, largely due to Dimon's "endless drills and strict discipline.

"[8] As commandant of Fort Rice, Dimon took a hardline approach to restricting illegal trade with the Native Americans, ordering the seizure of steamboats coming up the Missouri River and refusing to allow traders to pass without appropriate licenses from the army.

[8] On January 13, 1866, President Andrew Johnson nominated Dimon for the award of the honorary grade of brevet brigadier general, U.S.

In 1869, Butler founded the U.S. Cartridge Company in Lowell, Massachusetts, and secured major government contracts to produce small arms ammunition.