Charles O. Hamill was born in March of 1845 in Tyrone County, Ireland. Charles’ family immigrated to the United States in 1846 and Charles eventually settled in western Michigan, probably in Oneida, Eaton County.
Charles stood about 5’8” with blue eyes, fair hair and a fair complexion and was 18 years old and probably living in Oneida, Eaton County, Michigan, when he enlisted in Company D, 12th Michigan Infantry on November 1, 1861, at Grand Ledge, Eaton County, for 3 years, and was mustered on December 12, 1861, at Niles, Berrien County where the regiment was organized between December 9, 1861 and March 1, 1862. According to another source he enlisted on March 3, 1862 in New York State.
The regiment left Michigan for St. Louis, Missouri on March 5, and participated in the battle of Shiloh April 6-7, 1862. It was subsequently involved in the advance and siege of Corinth, Mississippi and by June 13 had moved to Jackson, Tennessee, where it remained until August when it moved to Bolivar, Tennessee. Charles was reported AWOL on September 29, 1862, at Bolivar; there is no further record of his service in that Regiment.
Apparently Charles returned to Michigan where he enlisted (listing his age as 22) in Unassigned, 3rd Michigan infantry on October 15, 1862, at Lansing for 3 years, crediting Oneida, but again, there is no further record -- there is no service record for him found in the 3rd Michigan records at the National Archives, nor is he found in the 1905 3rd Michigan Regimental history (although he is found in the 3rd Michigan regimental descriptive rolls.)
He also reportedly served in Company A, 1st U.S. Cavalry and he may also have briefly been a member of Battery A, 1st Michigan Light Artillery.
Charles may have returned to Michigan after the war. He reenlisted on January 6, 1879, in Company B, 1st U.S. Cavalry remained in the army (possibly in the 1st U.S. Cavalry) or reentered the army and by 1880 he was a corporal serving in the army and stationed at a post in Walla Walla County, Washington Territory. He was discharged on January 5, 1884 at Fort Cour d’Alene, Idaho. His character was reported as excellent.
After leaving the army Charles for a time as a miner. He was admitted as a single man (he listed his nearest relative as a brother Michael in Charlotte, Michigan) to the Pacific Branch National Military Home in Los Angeles, California, on April 7, 1897, and was still living in the NMH in 1900.
In 1885 he applied for and received a pension (no. 332139), for service in the 12th Michigan Infantry (and also listed service in the 12th Michigan Cavalry which did not exist during the war) as well as the 1st U.S. Cavalry.
Charles died on July 23, 1909, at the NMH and was reportedly buried in the National Cemetery in Los Angeles.