Charles was educated at Queen's College, Cork, where he took the M.D., M.Ch., and the obstetrical diploma of the Royal University, Ireland in 1882, also the F.R.C.S.I. in 1980. He entered the Army at the rank of Surgeon Captain on 2nd August 1884, then became Major on 2nd August 1896. During this time he served in Sudan 1885, where he received a medal, with clasp, and the Khedives's bronze star, and in 1896, advance on Dongola, and operations of 19th September. He then served in South Africa from 1900 to 1902 in Cape Colony and Orange River Colony, receiving the Queen's meal with one clasp and the Kings medal with two clasps. He retired on pay on 16th November 1904. At the outbreak of war, Charles rejoined and was employed in charge of the military hospital at Bower Barracks, Lancaster. He died at his residence in Lancaster. He was the youngest son of John Holmes of Athlunkard, co. Clare.