Charles Graham Halpine (Halpin) (pseud. Miles O'Reilly) (November 20, 1829 – August 3, 1868) was an Irish journalist, author and soldier during the American Civil War.
Born at Oldcastle, County Meath, he was son of the Rev. Nicholas John Halpin. He was educated at Trinity College, Dublin, until 1846, was originally intended for the medical profession, but he preferred the law, and in his leisure wrote for the press. The sudden death of his father and his own early marriage compelled him to adopt journalism as a profession.
In 1851 he emigrated to America, and took up his residence at Boston, where he became assistant editor of the Boston Post, and, with Benjamin Penhallow Shillaber, commenced a humorous journal called The Carpet Bag, which was unsuccessful. He afterwards resided at Washington, where he acted as the correspondent of the New York Times.
Removing to New York he secured employment on the Herald, and in a few months established relations with several periodicals. He undertook a great variety of literary work, most of which was entirely ephemeral. He next became associate editor of the ‘New York Times,’ for which paper in 1855 and 1856 he wrote the Nicaragua correspondence at the time of William Walker's filibustering expedition. In 1857 he became principal editor and part proprietor of the New York Leader, which under his management rapidly increased in circulation.
At the beginning of the American Civil War in April 1861, he enlisted in the 69th New York infantry, in which he was soon elected a lieutenant, and served during the three months for which he had volunteered. He was then transferred to the staff of General David Hunter as assistant-adjutant-general with the rank of major, and soon after went with that officer to Missouri to relieve General John Charles Fremont. He accompanied General Hunter to Hilton Head, and while there wrote a series of burlesque poems in the assumed character of an Irish private. Several of them were contributed to the New York Herald in 1862 under the pseudonym of "Miles O'Reilly", and with additional articles were issued in two volumes entitled Life and Adventures, Songs, Services, and Speeches of Private Miles O'Reilly, 47th Regiment New York Volunteers, 1864, and Baked Meats of the Funeral, a Collection of Essays, Poems, Speeches, and Banquets, by Private Miles O'Reilly, late of the 47th Regiment New York Volunteer Infantry, 10th Army Corps. Collected, revised, and edited, with the requisite corrections of punctuation, spelling, and grammar, by an Ex-Colonel of the Adjutant-General's Department, with whom the Private formerly served as Lance-Corporal of Orderlies, 1866.